Kirbie's Cravings

Keto Chocolate Lava Mug Cake

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.
overhead photo of spoon dipping into a chocolate lava mug cake

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.

close-up photo of chocolate mug cake

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.

photo of a spoon with a scoop of lava cake

overhead photo of a keto lava mug cake

Keto Chocolate Lava Mug Cake

Prep Time: 4 minutes
Cook Time: 1 minute
Total Time: 5 minutes
Course: Dessert
Cuisine: American
An easy low carb and keto-friendly molten chocolate cake that cooks in the microwave in about 1 minute.
5 from 4 votes

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, Cholesterol: 216mg, Sodium: 72mg, Potassium: 213mg, Fiber: 7g, Sugar: 1g, Vitamin A: 808IU, Calcium: 37mg, Iron: 2mg, Net Carbs: 5g

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!

Get new post updates via email

14 comments on “Keto Chocolate Lava Mug Cake”

  1. 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

  2. I was craving chocolate and carbs. This took care of both cravings without misbehaving! ?

  3. Very easy and good.  We used powered monk fruit sweetener since I did not have the other and it was perfect!!

  4. Excellent. Will make regularly. In my permanent list of recipes.

  5. I add a little more sweetner but this is AMAZING

  6. 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!

Leave a Reply

Your email address will not be published.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