Kirbie's Cravings

Brownie Mug Cake

This Brownie Mug Cake is rich, chocolaty, and fudgy. It comes together in just a few minutes and makes a delicious dessert, late-night snack or treat when you’re craving a fudgy brownie.

photo of a spoon with a bite of Brownie Mug Cake

I don’t know why but whenever the kitchen is finally clean, the first thing I do is make a mess. I don’t always mean to mess it up. For instance, I figured making a microwave mug brownie would be a minimal amount of tools, ingredients, and clean-up. But it took me six tries to get this one right, so you can imagine what the kitchen looked like after.

But all the effort was worth it because I am so happy with how this chocolate brownie mug cake came out. It looks so fudgy, doesn’t it? It’s a great easy dessert when you have a chocolate craving but you don’t want to make a whole batch of brownies.


  • Chocolate chips
  • Unsalted butter
  • Granulated sugar
  • All-purpose flour
  • Whisked egg

Chocolate chips: I like to use semisweet chocolate chips, but you can use milk chocolate or dark chocolate. If you use milk chocolate, your mug brownie will be sweeter. Dark chocolate will make it less sweet.

Sugar: For the best brownie, don’t change the amount of sugar. The amount is key to achieving the best fudgy texture for the mug cake. I also don’t have a substitute for the sugar. If you prefer a recipe with a granular sugar substitute, you might like my keto brownie mug cake.

Flour: I’ve only tested this recipe with all-purpose flour. When you measure it, be sure to spoon the flour into the measuring spoon and then level it off. This will ensure you don’t add too much. If you can’t use all-purpose flour, I have a flourless Nutella brownie mug cake you might like better. Or you can try the keto version that I linked earlier which is made with coconut flour.

Egg: You will only need about 1/2 an egg for this recipe. The easiest way to measure it is to whisk the whole egg in a small bowl and then measure out 1 1/2 tablespoons for the recipe. If you can’t have eggs, you should try my pumpkin brownie mug cake.

Brownie Mug Cake photo

How to Make It

Place the chocolate chips in a microwave-safe bowl that holds at least 6 ounces. Place the butter on top of the chips and melt them in the microwave for about 50 seconds. Whisk the melted butter and chocolate until smooth.

Whisk in the sugar, flour, and egg. Whisk really well until the brownie batter is smooth. All of the ingredients should be fully incorporated into the batter.

Microwave the mug brownie for about one minute. It’s done when it looks set on top, but still a little gooey around the edges.

Let it cool in the mug for 10 minutes before eating it. Or, for a fudgier texture, let it cool for 20 to 30 minutes.

Recipe Tips

Make sure you use a mug that holds at least 6 ounces. If it’s too small, the brownie batter will spill over the edges when it cooks.

The easiest way to mix the batter is by whisking. I use a small whisk, which makes it easier. If you try to stir the batter with a spoon, it will be much harder to combine. The chocolate makes it hard to tell if the egg is fully incorporated, so whisk vigorously to ensure everything gets combined.

Don’t overcook the cake. Start at 50 seconds and if the batter is still very wet, add a few seconds more.

This gooey brownie is very rich on its own, but you can add toppings like a scoop of vanilla ice cream, chocolate sauce, or some powdered sugar.

top-down photo of Brownie Mug Cake

More Easy Mug Recipes

Recipe now updated with video! You can also find all my recipe videos on my youtube channel.

Brownie Mug Cake

Servings: 1
Prep Time: 5 minutes
Cook Time: 2 minutes
Total Time: 7 minutes
Course: Dessert
Cuisine: American
This single serving brownie is rich, chocolaty and fudgy. It comes together in just a few minutes and makes a delicious treat, late-night snack or dessert.
4 from 1 vote


  • 1/4 cup semisweet chocolate chips
  • 2 tbsp unsalted butter
  • 1 tbsp granulated white sugar (see note)
  • 1 tbsp all-purpose flour (see note)
  • 1 1/2 tbsp whisked egg about 1/2 of a large egg


  • In a microwave-safe mug (use one that can hold at least 6 oz of liquid), add chocolate chips. Place butter on top of chocolate chips. Cover surface of the mug with paper towel and place into the microwave. Heat chocolate and butter at full power, for about 50 seconds if butter is cold or 40 seconds if butter is room temperature. Butter should be nearly completely melted when you're finished.
  • Gently whisk butter and chocolate with a mini whisk until chocolate is completely melted and smooth.
  • Add in sugar, flour, and egg. Whisk vigorously with a mini whisk until batter is smooth and ingredients are completely incorporated. Make sure you put some strength into the mixing. Because you're dealing with chocolate, it's harder to see if the egg is completely beaten in and you want to make sure all ingredients have been completely beaten together.
  • Microwave brownie at full power for about 1 minute. Brownie should look done but may be slightly gooey around the edges. Let brownie cool for about 10 minutes before eating. If you allow it to cool a little longer, about 15-20 minutes, it will actually have an even fudgier texture.



Tips for the Best Brownie Mug Cake
  • Please don't eliminate or lessen the sugar. The sugar does more than add sweetness it also helps create the fudgy and moist texture.
  • Make sure when you measure out the flour you measure flour the correct way by using another spoon to spoon flour into your 1 tbsp measuring spoon, and then level off the measuring spoon with a flat edge like the back of a knife, rather than just dunking your measuring spoon directly into the flour. Too much flour will make this cake dry and cakey.

The nutrition information provided are only estimates based on an online nutritional calculator. I am not a certified nutritionist. Please consult a professional nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.

Did you make this recipe?I'd love to see it! Mention @KirbieCravings and tag #kirbiecravings!

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4 from 1 vote

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Recipe Rating

36 comments on “Brownie Mug Cake”

  1. I loved this recipe to bits! Had so much fun times with the fam in the kitchen. Especially my little goofball of a three year. All fun and games until the little stinker started puking violently. No!! But What a tasty recipe especially with little chippers of chocolate!!!

  2. Hi, I’m about to try your recipe. I’d like to experiment by using dark chocolate (maybe 70% cocoa butter). Because I don’t normally buy chocolate chips. Another option may be to use some Dutch cocoa powder. How much should I use with either ingredient? Is it worth a try???

    • The dark chocolate should work fine but not sure about the cocoa powder – we haven’t tried that.

  3. May I ask what wattage microwave you have?

    And only 1 Tbsp of flour is used??

    Thanks, looking forward to making this!

    • Yes, that is the measurement for the flour. Please see the notes in the recipe card for the best way to measure it. Also, we use an 1100 watt microwave for our mug cake recipes.

  4. This is such a great recipe. I added a dash of salt and vanilla to it. I also put pecans and when it was done topped it with a sprinkle of coconut.

  5. OH MY GOSH! I’ve been looking for a mug cake recipie that isn’t sooooo dry and tasteless. This really fits and I don’t feel too bad while eating this as a treat. 10/10! This is by far the best mugcake ever and is worth the wait.

  6. Sooooo good I recommend. I personally hate mug cakes but this one is so goodddd!!

  7. Delicioussss.. I used 2 additional spoons of milk(like it lighter) and salted butter..yummy. Thanks for this recipe:D

  8. OMG! Ok, so I am currently in middle school and I just decided to try this recipe and may I tell you, this may be the bestmig cake I have ever had! (My other favorite is your Nutella mug cake) I love this recipe! I would totally this recipe to indulge in and it’s super simple. Also, I made mine with salted butter, and it worked just fine, to anybody that was wondering if it works the same. Thank you for blessing us all with this recipe! ???????

  9. Hello
    I tried this recipe and i liked it .Can powdered sugar be used in this recipe ?

  10. Is it ok to use regular salted butter?

    • I don’t recommend salted butter just because there is salt in there and depending on the amount of salt, it could make your brownie a little salty.

      • I have tired many many different mug cakes/brownies that I have found online in the past and I have to say that this recipe is the best by far! I whipped it up at home and then took it to my dad’s house and microwaved it there for dessert after dinner. They fell in love with it and ask me to bring it almost every time that I come over now. Thanks so much for this amazing recipe 🙂

      • thank you so much for sharing your experience! I’ so glad that you and your family like it!!

  11. Wow this was the best mug cake I’ve ever had! Thanks for the recipe!

  12. So, I doubled the recipe into a big bowl for a massive chocolate craving. May I just say, yum! Thanks for such an easy recipe.

  13. Can I use oil instead of butter? Thanks

  14. Warm, chocolatey deliciousness I don’t have to share with anyone? Okay, you twisted my arm. Looks amazing!