It’s been a rough couple of weeks at work, with no end in sight. As a result, not much baking has been happening.

Deadlines and a ton of work, while unpleasant, I can still handle. What I can’t stand is the yelling. Lots of yelling and unfair blame for anything and everything that goes wrong during the stressful period. The Boss yells. Because he can I guess. He yells for things out of our control, for things we should have anticipated even though he didn’t, for mistakes made on things we were never taught, etc. All the yelling has led to a really really tense environment.

When I’m in these stressful moments, I crave sweets like crazy. Chocolate, brownies, cookies, cake, anything. So even though I’ve been too exhausted for baking, I’ve been able to make these simple mug cakes to de-stress when I come home. A few minutes of mixing, and 2 minutes of microwave cooking and these are ready to be eaten.

After successfully making biscoff mug cake, I realized that I could apply the same recipe to a peanut butter mug cake. I have to say, even though peanut butter may not be my favorite flavor, the texture of this case came out so perfect, one of the best ones in my mug cake series.  Moist, fluffy, I couldn’t stop eating this.

This one baked up a bit higher than previous versions because the mugs I was using were too small. You definitely need either an oversized mug, or divide the batter into two regular sized mugs or else it will overflow. The smell of peanut butter while these cooked was quite nice too.

For an updated, lower calories and eggless version of this peanut butter mug cake, click here.

You can view my entire mug cake recipe collection here.

Update: If you enjoy this recipe, I just finished writing an entire book on mug cakes, featuring nearly 100 recipes.

To order the book, check out the list of online retailers.


Print Print Recipe

Peanut butter mug cake

Yield: 1

Prep Time: 5 mins

Cook Time: 2 mins

Total Time: 7 mins


4 tablespoons all purpose flour
4 tablespoons white granulated sugar
1/4 tsp baking powder
1 egg
3 tablespoons peanut butter
3 tablespoons milk
3 tablespoons vegetable oil

Note: I have an updated version of this mug cake here


Combine all ingredients in an oversized coffee mug. Whisk well with a small whisk until smooth. Microwave on high for 1 1/2 minutes and then take it out to check to see if it is done. If not, continue to microwave in thirty second intervals. Mine was done at 2 minutes. You don’t want to overcook it or it will become rubbery. You can also make this into two smaller-sized mugs. You can mix the batter all in one mug and then pour half into another mug. Make sure you cook each one individually.


91 Responses to “Peanut Butter Mug cake”

  1. Ju — January 31, 2012 at 12:55 am

    They look like souffles in a mug! ;) Sorry to hear about the stressful time you’re having. :( I hope things get better soon. x

    • Kirbie replied: — January 31st, 2012 @ 1:05 am

      I liked how it looks too! Even though it did overflow a little. You’re right, it does look like a souffle. Thanks for the nice wishes.

  2. Kay — January 31, 2012 at 6:49 am

    I hope work gets better too! I actually sort of like the overflow look of this mug cake :o)

    • Kirbie replied: — January 31st, 2012 @ 9:33 am

      I do too! At first I thought it looked lopsided and bleh, but then I really started to like it and didn’t want to break into it. I was eating this mini one I made with the leftover batter first.

  3. Ann P. — January 31, 2012 at 4:07 pm

    Oh dear, works sounds so tough to deal with; I’m very sorry :( I hope all of that is over and done with quickly, or at least that you get to eat a lot of these mug cakes and that you feel better!

    • Kirbie replied: — February 1st, 2012 @ 1:45 am

      Aw thanks. I didn’t mean to whine about my work, but I was trying to explain a little of what is going on in my life and why I haven’t written as much or baked as many complicated recipes. Your MCATs are over now right? So time to enjoy and have some fun?

  4. Kathleen — January 31, 2012 at 5:02 pm

    Hi Kirbie, would it be ok to substitute almond/soy milk in this recipe?

    • Kirbie replied: — February 1st, 2012 @ 1:46 am

      I haven’t tried it, but I think it should work.

  5. caninecologne — January 31, 2012 at 6:20 pm

    Sorry to hear about the tough times at work. We all need less stress in our lives, don’t we? The PB mug cake is something my husband would definitely enjoy. Plus it’s super easy to make. I may just whip one up tonight for him.

    • Kirbie replied: — February 1st, 2012 @ 1:47 am

      Hi CC, You know I was actually thinking of you when I made this. I thought it might be something you could make for your husband that he might enjoy. Let me know if you try it! I really liked it. The peanut butter seem to have just the right amount of oil/fat to create this perfectly fluffy and moist mug cake.

  6. Lianne — February 1, 2012 at 12:28 pm

    Hey Kirbie, I have tried you chocolate and peanut butter mug cake and loved it. But I was wondering what it would taste like if you made a peanut butter and jelly mug cake? I’m not sure it would work?

    • Kirbie replied: — February 1st, 2012 @ 1:52 pm

      Hmm, you mean mix the jelly directly into the batter? I think what might work is if you made the peanut butter mug cake, and then drop dollops of jelly in the middle (unmixed) and cook it. Though the jelly will end up being warm, but I think that might work better.

  7. caninecologne — February 1, 2012 at 3:56 pm

    hi kirbie – the cake came out pretty good last night. he ended up doing the mixing (and measuring), haha. So he pretty much made it himself.

    The cake was nice and fluffy and we used the crunchy pb, not the smooth. i want to do this again, but combined with chocolate!

    • Kirbie replied: — February 2nd, 2012 @ 8:58 am

      I’m intrigued by the idea of using crunchy peanut butter. I’ll have to try it out. If you have any more of the chocolate dreams peanut butter you can substitute with that for a chocolate peanut butter flavor. Or add cocoa powder.

  8. Ann P. — February 6, 2012 at 12:56 pm

    Replying to your comment above! ^ Yes! MCAT’s are over for me! Thanks so much for asking :) Tomorrow I’m heading off to Ghana for a mission trip, so I may miss a lot of the fun happening on your blog for the next 3 months! Very bummed about that, but I will try to pop in as often as possible! Internet access is pretty expensive there.

    • Kirbie replied: — February 6th, 2012 @ 6:39 pm

      I hope you have a fun and safe mission trip! I’ll definitely miss your comments on my blog.

  9. theminx — February 7, 2012 at 8:05 am

    Oh, I have to make this…I have a mug exactly like that one. :)

    • Kirbie replied: — February 7th, 2012 @ 9:32 am

      Oh that’s great! I hope you like it!

  10. Pam — February 8, 2012 at 6:49 pm

    Seriously – you are brilliant! The kids and hubby are in bed and I wanted a sweet snack. I made this Gluten Free with GF flour and viola – easy, single serve dessert! THANK YOU!

    • Kirbie replied: — February 9th, 2012 @ 9:24 am

      I’m so glad that it works with GF flour!

  11. Nicole — February 25, 2012 at 11:25 am

    This is my second mug cake to make. My first one (a recipe from another blog) was horrid, so I was afraid maybe all mug cakes would be horrid. This one wasn’t. :-) I did wish I had a bit of frosting for it though, but it’s good without it too. I’m going to try your strawberry one soon too. Thanks!

    • Kirbie replied: — February 26th, 2012 @ 9:23 am

      I’m so glad you enjoyed this one! I’m actually not much into frosting so these mug cakes are perfect for me. But I can see why you would miss the frosting. Maybe you can put some on top?

  12. Raven — February 26, 2012 at 2:02 am

    I just made this with white chocolate chips stirred in! It’s really good! :3

    • Kirbie replied: — February 26th, 2012 @ 9:26 am

      I’m glad you liked it!

  13. Katelyn — March 25, 2012 at 2:33 pm

    For the frosting you can just put any type of chocolate chips on top of it and it is great i put peanut butter chips on it and it was very peanut buttery but GOOD

    • Kirbie replied: — March 26th, 2012 @ 9:12 am

      Great idea!

  14. Jess — March 31, 2012 at 7:12 am

    Its 1am and I just made this. I feel like I should be phoning my mother and asking WHY I’ve gone my whole life up until this point with no mug cake! It was so quick and easy. The bottom of mine was a little gooey but I liked it like that. Next time I might cut 10-20 seconds off the microwave time. Awesome late night (drunk) food!

    • Kirbie replied: — April 1st, 2012 @ 10:47 pm

      Yeah my bottom is usually gooey too. I think it’s hard to avoid with mug cakes. But oh so good. I’m so happy I discovered it. Though it makes dessert a little too accessible now.

  15. Nathaniel — May 18, 2012 at 11:12 am

    Replaced the required amount of sugar and oil with Splenda and Apple Sauce, respectively. Turned out very well! Thanks for the recipe.

    • Kirbie replied: — May 18th, 2012 @ 12:31 pm

      Interesting. Glad to hear it worked with apple sauce!

  16. Kalli — June 26, 2012 at 4:41 pm

    This is the first mug cake I’ve ever tried and omg, so easy and delicious! I used crunchy PB, since that’s all I had, and I loved all the little crunchy bit of peanuts. Also, I was lazy and just used a glass measuring cup instead of a mug, but it worked! Thanks for the recipe, I’ll have to try the other flavors you have!

    • Kirbie replied: — June 26th, 2012 @ 7:51 pm

      So glad you liked! The PB is one of my favs, along with the nutella, flourless nutella, and brownie ones.

  17. Jessie — July 18, 2012 at 8:26 am

    Just made this, put a touch of chocolate syrup on top, delicious! :D

  18. Ann — January 1, 2013 at 9:03 pm

    I was out of milk, so I used vanilla greek yogurt instead. With a little extra cooking time, it’s definitely still incredible. Thanks for putting together such an easily adaptable recipe!

    • Kirbie replied: — January 2nd, 2013 @ 9:38 am

      Nice to know it still worked with the greek yogurt!

  19. mub — January 2, 2013 at 4:53 am

    I used a really big mug and it still over-rose and dribbled down the sides. After I cleaned up my microwave mess it tasted great… haha!

    • Kirbie replied: — January 2nd, 2013 @ 9:29 am

      I’m glad it still tasted great. Sorry yours dribbled over though.

  20. Angele — January 10, 2013 at 7:39 pm

    I made this peanut butter one. It was a bit bland. After it was cooked, I topped it with some strawberry jelly and it tasted just like a warm PB&J. Yum!

    • Kirbie replied: — January 11th, 2013 @ 10:06 am

      Nice topping choice!

  21. Chinwe — January 26, 2013 at 8:45 am

    OMG!!!! I just whipped this up in less than 10 mins. I can’t believe it was that easy. I had some white chocolate buttercreme frosting on hand and lets just say the combo is a match made in heaven.
    I’ve found my new true love!!!!!!
    Thank you, thank you so much!!!

    • Kirbie replied: — January 27th, 2013 @ 11:57 pm

      Haha. You’re welcome!

  22. Margarete — February 12, 2013 at 4:51 pm

    Thanks for those awesome recipes. I made the pure Nutella one last night. Just perfect for hubby and me, hubby loved it. Tonight it’ll be the peanutbutter one. Thank you so very much

    • Kirbie replied: — February 12th, 2013 @ 10:03 pm

      I’m so glad you enjoyed the Nutella one and I think you’ll like this pb one too. Thanks for taking the time to leave a nice comment. =)

  23. Sarah — May 12, 2013 at 11:24 am

    I made this and I have to say this is the best mug cake I’ve ever made!! All the other ones had a crumble texture and not overflowed like the pictures they showed. I like it when it’s over filled and this is the first one that did! It SO good! It’s moist and fluffy and I didn’t have to run to the store to get any if the stuff cuz it’s just laying in the kitchen! It’s so.. Well it’s just amazing!! I can’t put it down!! I’m sorry to hear about all the trouble hope it gets better

    • Kirbie replied: — May 13th, 2013 @ 9:22 am

      This is one of my favorites. Peanut butter makes a really good mug cake. Glad you enjoyed it.

  24. Jade — May 16, 2013 at 7:09 pm

    I just made this with the addition of a pinch of salt and a dash of vanilla, and it was delicious! Only microwave cake I’ve made (I love cake, so I’ve made a lot. Mmm, cake.)that actually has great texture. Thanks for the recipe!

    • Kirbie replied: — May 17th, 2013 @ 12:19 am

      Glad you like it!

  25. Angela — May 18, 2013 at 3:23 pm

    It’s the first time my mug cake was successful- because I baked it in a large bowl instead! I substituted the vegetable oil with olive oil and used crunchy peanut butter. The bottom was still uncooked after 1 minute and 30 seconds, so I turned over the cake and popped it back into the microwave for another minute. Turned out great!

    • Kirbie replied: — May 18th, 2013 @ 11:38 pm

      Oh, cake in a bowl. Interesting. Glad it turned out well!

  26. vanessa — May 23, 2013 at 3:20 pm

    hey kirbie , can I leave out the baking powder or no? i need this question answerd ASAP!!!!!!!!!!!!

    • Kirbie replied: — May 23rd, 2013 @ 11:40 pm

      If you leave out the baking powder the cake wont be able to rise.

  27. kathy — July 20, 2013 at 5:58 pm

    Do you know what the calorie content is?

  28. Caitlin — January 2, 2014 at 9:25 pm

    in the microwave as we speak! Cannot wait!

    • Kirbie replied: — January 3rd, 2014 @ 12:08 am

      hope you love it!

  29. John Smith — January 27, 2014 at 10:39 pm

    I feel like there is too much egg in the cake? Would it be OK if I just added half of an egg? Thanks. Sorry about the work by the way.

  30. Sammie — February 8, 2014 at 11:21 pm

    hi Kirbie! I was wondering if we can replace vegetable oil with something else. Will olive oil work? please reply ang give suggestions, thanks!

    • Kirbie replied: — February 10th, 2014 @ 1:47 am

      You can probably use canola oil. I don’t know about olive oil though. I’ve tried making some other mug cakes with olive oil and it came out wrong. Also, this is an older recipe. While it does taste good, I’ve made another version that doesn’t use additional oil or eggs. So you can try this one (and you can leave out the jam if you just want plain peanut butter mug cake)

  31. Beth — April 22, 2014 at 10:18 am

    Definitely share this with a friend, it overfilled my 12 ounce cappuccino mug! I didn’t have one, so I *had* to eat it all myself, darn the luck. lol It was a little crumbly and I would’ve liked just a bit more peanut butter flavour (that’s me, I’m a PB freak), but I’ll definitely make it again. Maybe next time I’ll whip up some peanut butter frosting for it. There will be a next time.

    • Kirbie replied: — April 22nd, 2014 @ 1:11 pm

      I have this eggless pb one that i made more recently which I think may have a more pronounced PB flavor and should fit easily in a 12 oz
      Sorry yours overflowed. I usually recommend 14-16oz mug. 12 oz works for most, but it’s sort of the minimum oversized mug you need, so for certain recipes, it will overflow.

  32. Tara — May 22, 2014 at 3:48 pm

    Love this recipe!! I’ve been using it for almost 2 years and still not tired of it! First time commenting on it though… lol

    • Kirbie replied: — May 23rd, 2014 @ 1:26 am

      awesome! You should try some of the other mug cake recipes if you haven’t already!

  33. Laaibah — June 17, 2014 at 9:35 pm

    It’s simply amazing how such simple ingredients were used to create something so delicious, and that too in just a few minutes! Tasted perfect! Great job.

    • Kirbie replied: — June 18th, 2014 @ 12:48 am

      glad you enjoyed it!

  34. Brit — June 30, 2014 at 8:37 pm

    Absolutely delicious! I put a paper towel under the mug for the spillover. Amazing dessert :D

    • Kirbie replied: — July 1st, 2014 @ 11:42 pm

      glad you like it!

  35. Leila — September 6, 2014 at 6:08 am

    amazinnggg! i tried this and i took a taste right from the microwave and i ended up eatin half of it right from the micro!

    • Kirbie replied: — September 6th, 2014 @ 7:22 am

      awesome! =)

  36. Jennifer — September 6, 2014 at 5:48 pm

    Very yummy! Thank you!  I did not use all purpose flour. I used 2 tablespoons of coconut flour and 2 tbsp of almond flour (to make it gluten free) and it was fabulous. Very light and fluffy! Oh..and I added a small handful of mini chocolate chips.  Thanks for the recipe!!

    • Kirbie replied: — September 6th, 2014 @ 10:44 pm

      im glad you made it and enjoyed it!

  37. Hannah — September 8, 2014 at 7:59 pm

    OMG! This is the best mug cake recipe iv’e tried, so delicious! and it looked really cute in my over-sized tea cup! will definitely be making this cake again thanks for the recipe! :) 

    • Kirbie replied: — September 9th, 2014 @ 12:03 am

      i’m so glad you like it so much!

  38. Hanan — October 29, 2014 at 7:01 am

    Hi ! I just tried this but it turned out VERY dry !!! Idk why :((( 

    • Kirbie replied: — October 29th, 2014 @ 8:38 am

      this recipe should not be dry at all. did you follow it exactly? did you use regular pb and not natural pb? natural pb usually is chunkier and drier and might not work

  39. Alex — November 13, 2014 at 11:58 am

    Is this mug cake a single serving? Because it’s over 700 calories. It looks great and easy, but I’m not sure I can justify 700 calories on “slice” of a mug cake.

  40. Jim — February 8, 2015 at 2:22 pm


    Just made this and it’s delicious although the cup I used was too small! Just to say that I made it with self-raising flour and used coconut oil and it worked perfectly although I did give it 2 mins in the microwave just for it to really be cooked through.

    However I do have one question. I’m on a low sugar diet so I’m wondering if this would work with a pourable artifical sweetener instead of the sugar? Is the sugar purely there for sweetness or is it doing something to the mix during the cooking that the artifical sweetener wouldn’t? I’d probably use less of it as I don’t mind a slightly less sweet taste.

    Also same question about the eggless version which I think would be even better again for my regieme.

    • Kirbie replied: — February 9th, 2015 @ 12:52 am

      The sugar is there just for sweetness, though if you are going to substitute, I wouldn’t use a liquid one because then you will have too much liquid in your batter and it likely won’t cook right. PS, the updated recipe also has less sugar too.

  41. Megan Romero — March 8, 2015 at 5:09 pm

    My 11 yr old found and made this tonight (with help) and is in heaven.. Fyi his hamater snuck some  bites too lol 

    • Kirbie replied: — March 9th, 2015 @ 12:34 am

      lol! I think this is the funniest thing I’ve heard in awhile. I totally have this image in my mind of this adorable hamster. I wish you had a video!

  42. Catherine — March 14, 2015 at 11:11 am

    so I made this mug cake and I honestly did not like it at all… I do however love your peanut butter and jelly mug cake!

    • Kirbie replied: — March 15th, 2015 @ 8:30 pm

      the pb &j is an updated version of this one. I think this one is still fine, it’s quite rich though, which is why I created a newer one

  43. JustHeather — March 31, 2015 at 10:53 pm

    I’m so glad I found this recipe. I love it! And it’s all mine when I make it because my husband doesn’t like pb.

    (I’m sharing your link on my blog so others can have this wonderful recipe too.)

    • Kirbie replied: — April 1st, 2015 @ 8:41 am

      I’m so glad you enjoyed the recipe!

  44. Rio Francisco — November 3, 2015 at 1:00 am

    hi Kirbie. I am a fan of your blog and I have to say you inspire me a lot on your mug cake recipes. I have tried this  recipe and it was really good.  Thank you so much.  you can see my mug cakes here on my blog :)

    • Kirbie replied: — November 4th, 2015 @ 8:52 am

      I’m happy to have inspired you!

  45. Justinian Adolfus — November 3, 2015 at 2:50 pm

    Just made this and it’s awesome, thank you tbh fam, you are the best mugcakiërstein on the internet

    • Kirbie replied: — November 4th, 2015 @ 8:52 am

      aww, thank you!

  46. Elise — March 30, 2016 at 12:19 pm

    This did not work for me… I followed the instructions and everything im just really unsure what i did wrong

    • Kirbie replied: — March 31st, 2016 @ 10:45 am

      Can you please provide a little more explanation when you say it didn’t work? Then I might be able to help pinpoint the problem. Did it not cook? not rise? too dry? too hard? etc

Leave a Comment

Leave a Comment

Your email address will not be published. Required fields are marked *

Thank you for submitting a comment! Please note, all comments are held in moderation until owner approval.

Current day month [email protected] *