This Keto peanut butter mug cake is a super indulgent, super easy dessert. And it proves the well-known fact that life is just BETTER with peanut butter!
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I love mug cakes, because they deliver almost instant gratification.
There you are, thinking: "Wouldn't it be lovely to eat something sweet right now?" So you stir up a few ingredients and stick it in the microwave.
And less than five minutes later you're tucking into a warm, comforting keto peanut butter mug cake. It's almost too good to be true!
All equally gorgeous, ridiculously simple and delightfully sugar-free. Take your pick according to your craving of the day!
Keto mug cake ingredients
It is possible to make a totally flourless pb mug cake with only peanut butter, egg, sweetener and a little bit of baking powder. This combo was a bit firm for my taste, especially once cooled. (Incidentally, it makes incredibly crunchy peanut butter cookies).
To fluff it up, I added some coconut flour and a good measure of double cream. These additions make the mug cake taste like a REAL, moist cake. Yum.
Which peanut butter to use
Try and source peanut butter that is unsweetened. Good peanut butter really only needs to contain 1 ingredient - peanuts.
Both smooth and crunchy peanut butter work in this recipe - use whichever you prefer!
Carbs in peanut butter
Even though peanuts are technically a legume, they are high in fat and low in carbs - just like nuts. This makes pure peanut butter a great keto food. 1 tablespoon of contains 3.2g net carbs.
Not all peanut butter is keto friendly though. Always read the ingredients when you shop - some brands add sugar or inflammatory vegetable oils.
Which chocolate chips to use
The chocolate chips are optional - the low carb mug cake tastes just as good without. However, we all know that chocolate and peanut butter are a dream team 🙂
I used a chocolate with 90% cocoa solids for my cake, which I chopped. If possible, your chocolate should contain at least 85% cocoa solids.
How to make a keto peanut butter mug cake
1.) Choose a tall vessel for microwaving. You want to have at least 3 fingers space at the top. Mug cakes have a habit of rising and can spill over the top.
2.) Mix all ingredients with a fork inside the cup - and microwave. That's it!
3.) Enjoy as is of top with sugar free keto whipped cream, peanuts and shaved chocolate.
Tip: To avoid a mess, you can pause the microwave to check after about 50 seconds. If necessary, continue cooking the cake in 10 second bursts. This will prevent spillage as you’re giving the cake time to sink back down in between.
Possible add-ons for this cake: ½ tsp vanilla extract or 1 tsp cinnamon.
To make this low carb keto mug cake dairy-free, simply use coconut cream in place of the double / heavy cream.
If you prefer cakes with almond flour, use ¼ cup or 4 ½ tbsp almond flour instead of the coconut flour.
Ran out of peanut butter? You can use almond butter or any other nut butter in this recipe.
This PB mug cake is VERY FILLING. Personally, I think it’s perfect for sharing. If you don’t want to spoon from the same cup, simply divide the mix between 2 ramekins.
How to cook this cake in the oven
Don't have a microwave? Simply cook the mug cake in the oven. Use oven proof ramekins and bake at 180 Celsius (350 Fahrenheit) for 10 -12 minutes.
Storing low carb mug cake
You can store this keto mug cake with peanut butter in the fridge for up to 3 days or even freeze it.
If you decide to divide the batter between 2 ramekins and eat one cake straight away and one the next day, I recommend that you refrigerate the second portion as a batter. Then, cook it straight before eating.
Tried this recipe? Give it a star rating below!
Keto Peanut Butter Mug Cake
Note: The servings slider only changes the first amount in each line and not any subsequent amounts. Please make your own calculations where necessary. ***As an Amazon Associate I earn from qualifying purchases.
- Mix all ingredients in a tall glass or cup, using a fork. Fold in the chocolate last, if using.
- Microwave on high for about 90 seconds.
This post was first published in May 2019. It was updated and republished in January 2021.
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