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This chocolate lava mug cake cooks in the microwave in about 1 minute. It’s rich, chocolatey, with molten chocolate inside. Plus it is low carb, gluten-free and keto-friendly.
Just in time for Valentine’s Day, I wanted to share this easy dessert. I previously made keto lava cakes before and while I love those, I wanted to create a microwave mug version. This recipe is easy with minimal clean-up. Plus you don’t need to wait for the cake to bake in the oven.
Highlights
- The chocolate cake uses the same ingredients I would normally use to make a molten chocolate cake. It is flourless and very rich and chocolatey.
- Because of how quickly a microwave cooks the cake, it doesn’t have a natural molten center. Instead, chocolate squares are added to the center of the batter, which stay melted when the cake is cooked.
- The melted chocolate will be closer to the bottom of the mug, but it’s easy to dig deep into the cake, or you can turn the cake upside down onto a plate to enjoy.
- You can undercook the cake slightly so that the edges are still gooey, allowing for even more molten chocolate.
- The cake tastes great with a scoop of ice cream, whipped cream, or sugar free chocolate syrup.
Ingredients
- butter
- heavy cream
- egg
- unsweetened cocoa powder
- powdered erythritol
- sugar-free chocolate squares
Cooking Tips
- Make sure to follow the steps listed for mixing the ingredients in the order I list in the instructions. It will make whisking the batter much easier. If you try to add too many ingredients at once, it will be difficult to mix the batter and you may end up with lumps of cocoa powder.
- You can use dutch process or natural cocoa powder. I prefer dutch process because of its richer color and flavor.
- Make sure to use powdered erythritol and not granular. Granular will not have enough time to melt with the short cooking time. If you don’t have any powdered erythritol on hand you can easily grind up the granular in a food processor to make it powdered.
- I prefer a more bittersweet dark chocolate cake, but if you want something sweeter, increase the amount of erythritol you add to the cake batter.
You might like my keto chocolate cake, too!
Keto Chocolate Lava Mug Cake
An easy low carb and keto-friendly molten chocolate cake that cooks in the microwave in about 1 minute.
Ingredients
- 1 tbsp unsalted butter melted
- 1 tbsp heavy cream
- 1 large egg
- 2 tbsp unsweetened cocoa powder
- 2 1/2 tbsp powdered erythritol
- 2-3 sugar-free semisweet or dark chocolate squares 1 inch by 1 inch
Instructions
- Add melted butter and heavy cream to a microwave-safe mug. Whisk until fully combined.
- Add egg and whisk until batter is smooth. Make sure there are no egg white streaks.
- Add half of the cocoa powder. Whisk until cocoa powder is completely mixed into the batter and no lumps remain. Add in remaining cocoa powder and mix until batter is smooth. Batter should be getting thick.
- Add in erythritol. Whisk until evenly mixed into batter.
- Place chocolate squares onto the center of the batter and gently push in until they are just covered. Don't push too far because they will sink when the cake cooks.
- Cook cake in the microwave at full power for about 1 minute or until the middle of the cake puffs up, the cake has pulled away from the edges of the mug and is only slightly gooey around the edges.
- You can top the cake with ice cream, whipped cream, sugar-free syrup or powdered erythritol. Enjoy cake while still warm. The melted chocolate center will be closer to the bottom half of the cake. If you want easier access to the chocolate center, you can also flip the cake upside down onto a plate. This will also allow all the melted chocolate to pour over the cake. Enjoy the cake while it is still warm.
Notes
- I used a 1100 watt microwave. If your microwave has a significantly different wattage, you may need to adjust cooking time or power.
- The cake will not rise too high so an 8 oz mug should be large enough to cook the ingredients in without the batter spilling over.
- I prefer a bittersweet dark chocolate cake. If you prefer something sweeter, you may want to add a little more erythritol to the batter.
- Make sure to use powdered erythritol and not granular. Granular will not have enough time to melt with the short cooking time. If you don't have any powdered erythritol on hand you can easily grind up the granular in a food process to make it powdered. Powdered Swerve will also work.
- Make sure to follow the steps listed for mixing the ingredients in the order I list in the instructions. It will make whisking the batter much easier. If you try to add too many ingredients at once, it will be difficult to mix the batter and you may end up with lumps of cocoa powder.
- Your chocolate squares should be about 1 inch x 1 inch. I used Lily's chocolate.* If you use their bars, 2 of the small rectangles is about 1 inch by 1 inch.
- You can add 2-3 (one-inch) squares depending on how much melted chocolate you prefer. I found 2 (one-inch) squares to provide a decent amount of chocolate inside. 3 will cause more chocolate to sink to the bottom but then I just flip the cake over onto a plate and spread the chocolate across the surface.
- *Some of the product links contained in this post are affiliate links. Much like referral codes, this means I earn a small commission if you purchase a product I referred (at no extra charge to you).
- The estimated nutrition carbohydrates count excludes sugar alcohols. The net carbs excludes both fiber and sugar alcohols.
Nutrition
Serving: 1cake, Calories: 290kcal, Carbohydrates: 12g, Protein: 9g, Fat: 27g, Saturated Fat: 16g, Sodium: 72mg, Fiber: 7g, Sugar: 1g, NET CARBS: 5
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!
What if I don’t have erythritol
Another commentor mentioned they used stevia – hope that helps!
So yummy, turned out perfect
So glad you loved it!
This the best chocolate dessert! I am a diabetic and this is so decadent ????
We’re glad you loved it!
To.Die.For.This was SOOOO good! (I’m studying Hebrew on Duolingo, and they keep repeating sentences about cake. Take cake is delicious. This is a delicious cake. Then…I crave cake! Glad I can do a keto cake with very low carbs (not even any almond flour!) to divert and satisfy the craving my language lessons create!
We’re happy you loved it!
Would like to know if it works with liquid stevia.
Sorry, but we haven’t tried that.
I enjoyed the recipe, but I’m wondering where the 7 grams of fiber is coming from. Can you give us more details?
It’s mainly from cocoa powder and chocolate. Hope that helps!
Soooooooo good!! Light, chocolatey and oh so delicious. Thank you for sharing.
I’m so glad you liked it!
Can I replace the microvawe with oven? If yes,what temperature and for how long?
I have not tried this in the oven. However I do have a keto lava cake recipe designed for baking: https://kirbiecravings.com/keto-lava-cake/
This taste amazing! Thank you for this recepie! 🙂
I’m so glad you liked it!
This Desert was Amazing!
I served it with some whipped cream and cinnamon sprinkled on top! Best Keto Desert I’ve had!
I’m so happy you enjoyed it so much!
Thank you, just got this jewel in my email!! Keto, sweety, mouth watering, chocolatly, and low calorie. This recipe is any dieters’ dream!!
We hope you love it!
WOW!!! I love lava cake and I’m so happy I found this recipe. It is so good and healthier in my mind. A guilty pleasure that I’m okay with.
Thank you.
I’m so glad you liked it!!
DELISH and very rich. All I had were the main ingredients and instead of chocolate squares, Lily’s dk choco chips….they were gooey and this was a winner! Will do again!
I’m so glad you enjoyed!
This is the best keto recipe I have ever tasted.
aww, thank you for the kind words!
Oh dang, that was seriously amazing! What I really love is that you don’t miss or need the extra bulk and carbs of nut flour. This was fantastic. Used Lilly’s salted Dark chocolate almond squares for the molten. Grinded a pinch of pink Himalayan on top followed by SF whipped cream. And a strawberry. ? Perfect! Thank you
I’m glad you liked it!
Turned out well, even though had to make substitutes. Didn’t have heavy cream, so I used half and half creamer. Didn’t have erythritol, I used Splenda. Didn’t have chocolate squares, I used 5 chocolate chips. For the cocoa powder, I used one tbsp Special Dark Hershey’s Cocoa and one tbsp regular Hershey’s Cocoa (I do this with all my recipes needing cocoa powder)
Great recipe!
I’m glad you enjoyed!
I add a little more sweetner but this is AMAZING
I’m so glad you liked it!
Excellent. Will make regularly. In my permanent list of recipes.
I’m so glad you enjoyed!
Very easy and good. We used powered monk fruit sweetener since I did not have the other and it was perfect!!
I’m so glad you enjoyed!
I was craving chocolate and carbs. This took care of both cravings without misbehaving! ?
So glad you were able to get your chocolate and carbs fix without going off your diet!
My wonderfully lovely neighbour is enduring cancer treatment and using a quite strict keto diet, but does have a sweet tooth so this recipe is a godsend. Thank you
I hope your neighbor enjoys the recipe