This low carb molten chocolate cake takes less than 5 minutes to make because you make it in the microwave. This easy, low carb dessert would be perfect for Valentine’s Day or when you have a chocolate craving. Only 4.9g net carbs.
You might also like this microwave low carb pumpkin pie for one recipe.

I’m obsessed with mug cakes. I’ve been trying to make a good one for so long and I’ve finally did it! This low carb molten chocolate cake only takes about 5 minutes to make and tastes fantastic. It’s really chocolatey and the center is ooey and gooey.
Best of all, you can make it in the microwave and it’s only 4.9g net carbs. I have to admit I’ve been making these a lot and now I’m moving on to a peanut butter one. I’ll keep you posted on that one.
Low Carb Dark Chocolate To Use
I have other mug cake posts on here like my 1 minute pumpkin muffin. That recipe is great for a quick breakfast or snack. But this one is much more decadent.
One of the reasons it’s so gooey in the middle is that I put a piece of dark chocolate in the middle. I used the chocolate bar below that I buy at Aldi.
The package contains 5 smaller bars and each of those has 6g net carbs. In this recipe I only used ¼ of those small bars which is about 6-7 grams. That’s all you need. As a matter of fact you don’t even need that if you don’t have any.
Try With Or Without Chocolate Bar
One of the first batches I made I didn’t use the chocolate and you can see that pictured below on the left. It was still gooey in the center but not as much as the other one pictured on the right. When I make this now I usually make the one on the left to save a few carbs. You can decide which you prefer.
Low Carb Molten Chocolate Cake Recipe
This should only take a few minutes to whip up. Start by adding butter to a ramekin and microwave for 30 seconds. Swirl it around the ramekin to sort of grease the sides.
Next add in the cocoa powder, Swerve sweetener, stevia and cream and mix well. Add in the egg yolk and mix well. Take the piece of chocolate, break into littler pieces and press down in the center of the cake mixture.
Microwave for 30 seconds and then let cool for a few minutes before eating. It should look like the picture below.
I think these would be great for a Valentine’s Day dessert. You can always add a bit of homemade whipped cream or a few slices of strawberries, but it’s delicious as is. Or for a whole cake try my friend Vicky’s keto flourless chocolate cake.
The nutritional information for 1 serving is:
with chocolate bar 422 cals / 42.9g fat / 39.7g carbs / 34.8g fiber / 3.3g protein = 4.9g net carbs
without 382 cals / 39.6g fat / 37.5g carbs / 34g fiber / 2.6g protein = 3.5g net carbs
If you would like to see some of my favorite baking products that I buy on Amazon, you can find them here along with other items I use for low carb cooking and baking.
Keto Molten Chocolate Cake in the Microwave
This low carb molten chocolate cake takes less than 5 minutes to make because you make it in the microwave. This easy, low carb dessert would be perfect for Valentine's Day or when you have a chocolate craving.
Ingredients
- 2 tablespoons butter
- 2 tablespoons cocoa
- 2 tablespoons Swerve sweetener
- 1 egg yolk
- 2 tablespoons heavy cream
- ¼ bar chocolate**(~6-7 grams 85% dark chocolate)
- 10 drops liquid vanilla stevia
Instructions
- Add butter to a ramekin and microwave for 30 seconds.
- Add in cocoa powder, Swerve sweetener, stevia, and cream. Mix well.
- Next add in egg yolk and mix well again. Take the small piece of chocolate and break into small pieces. Add to the center of ramekin and push in with finger.
- Microwave for 30 seconds. Let stand for a few minutes and then eat. The middle should be melty and the sides should be cooked. Do not cook for more than 30 seconds.
- ** I used a ¼ of a bar of 85% cacao chocolate that I get at Aldi. See picture in post. If you are substituting another chocolate make sure it is low in carbs. You only need a little, tiny bit. You can also forgo this step completely and it will still be delicious.
Nutrition Information:
Yield: 1 Serving Size: 1 ServingsAmount Per Serving: Calories: 422Net Carbohydrates: 4.9g
Veena Azmanov
Delicious and easy and quick too. A dessert to be loved by all.
Mary
Can I use milk if I don’t have heavy cream?
Denise
Hi Mary, you can use milk but it will have more carbs. If you don’t care about the carbs that will be fine. Hope you like it!
Gloria
This is amazing!!! Was…
thank you so much for this fantastic recipe. Made it in microwave.
Have the perfect texture and flavour and so easy to make.
Denise
Hi Gloria,
So glad you liked it! I was eating them everyday for awhile there. Thanks for coming back to comment… I appreciate it!
Cheryl Dillenbeck
I only have liquid stevia plain-not vanilla-will it make a big difference in the recipe and taste? Is there something I can substitue? like add more Swerve and use vanilla extract 10 drops?
Denise
Hi Cheryl, I don’t think it will matter much. You can add a little vanilla extract if you want but I wouldn’t sweat it. I just love that vanilla stevia as it seems to take a little of that bitterness that stevia usually has. But honestly it won’t make much of a difference if you just use plain. Good luck!
Vex
This literally changed my life. Thank you, seriously everyone I’ve showed this too love it. I just cook it for a minute in 30 second intervals to make it more like a brownie. Again, thank you, seriously
Denise
Hi Vex,
Thanks so much for letting me know! I make these things and I really like them but I never know if others will. I just made a pumpkin version similar to this and it is goooood! Ill be posting it soon so if you like pumpkin you will like this one too.
Julue
Fantastic recipe. The mug works great. Easy. Delicious. Really delicious. And I’ve made quite a few of these keto mug cakes, and this one is undoubtably my favorite.
Denise
Hi Julie,
So glad you like it! Thanks for taking the time to comment!
Helen @ Fuss Free Flavours
So delicious and so tempting to make all the time. I love those mini bars in a bar from Aldi.
Denise
I love those mini bars too! Thanks for taking the time to comment!
Marisa Franca @ All Our Way
I love easy desserts and I hate them at the same time. It tempts me to make and eat them. That chocolate molten cake looks too good to be true. Ooey, gooey and chocolatey at the same time. Just hand me a huge spoon.
Denise
I know what you mean Marisa! A love/hate affair!
Michelle
Oh wow this sounds so good! I love molten chocolate cakes and the low carb makes it so tempting to make it all the more often!
Denise
Thanks Michelle! I love a good chocolate dessert….especially it’s low carb. 🙂
Veena Azmanov
I love microwave cakes..! So easy, no left over and so quick. But the best part I love warm cakes especially with ice cream so often I like making a quick microwave cake with ice cream..This look so good. yum!
Denise
Oh that sounds good!
Jolina
I absolutely love mug cakes too. Sometimes I’m craving for cake and baking a regular sized one is just not practical. I have my favourites but I haven’t found a chocolate recipe that I love yet. I think this will be it! So gooey and chocolatey!!
Denise
Thanks Jolina! I have been making too many of these lately because they are so yummy. 😉
Gloria @ Homemade & Yummy
I love easy desserts. This looks like a chocolate lovers dream (like my hubby). What a great way to whip up a special treat any time you like….maybe a little too easy (LOL). In like I would be making this ALL the time.
Denise
Haha I know what you mean Gloria. I was making 1 a day for a while there “trying to get the right taste” haha!
Debbie
Guess what I am going to make tonight!!!
Denise
I ate so many of them last week LOL!
Debbie
If I don’t have a ramekin, what do you suggest I use instead?
Denise
Any microwaveable bowl that’s about 2 cups. You can try a mug though I have not tried that yet. I like the ramekins because they are wide and shallow. I’m going to go make one in a mug and let you know how it goes!
Denise
I worked fine. It doesn’t rise very much but it tastes great. I made it without the chocolate bar and it was still nice and gooey inside. Good luck!