This peanut butter keto mug cake takes only minutes to make! It’s tender and lightly sweetened, and makes a wonderful easy breakfast or dessert.
Sometimes I create recipes with a specific outcome in mind. And sometimes I throw together some ingredients on a whim and hope for the best. This keto mug cake recipe falls into the latter category!
But while it was rather slapdash in its creation, it quickly became a fan favorite recipe. And a family favorite too! I often whip these little keto cakes up when we need a quick treat.
You know that I take peanut butter and chocolate very seriously. And many of my recipes are quick and easy, like Keto Peanut Butter Bars and easy Peanut Butter Protein Balls. So you can rest assured that these easy mug cakes are good stuff!
Why you will love this recipe
Mug cakes have appeal because they are so easy to make. But they can also have a bit of an odd texture from the fast cooking method. They tend to end up a bit spongy.
These keto peanut butter mug cakes differ in that regard. There is something about the addition of peanut butter that gives them a proper cake texture. And yet they take only about 5 minutes to make.
They really are super family friendly and since this recipe makes six, you can feed the littles and yourself. You can also scale the recipe back and make only three servings, which is more appropriate for those who live alone or are doing keto alone.
And these easy cakes store quite nicely. I do recommend cooking them all at once, as the batter thickens if it sits too long. But you can store the finished keto mug cakes in fridge and re-warm them easily when you want another serving.
Reader Reviews
“These are the Creme de la Creme of mug cakes….my all time favorite (and I am beginning to be way too familiar with mug cakes). But the peanut butter adds some density so that these are not just fluff on a spoon. There is just the right amount of substance….and the flavor is FABULOUS. Caroline, you are amazing. You obviously put a lot of testing into your recipes because they are the gold standard in my opinion. thank you for putting food worth eating on our low carb table.” — Deborah
“I was skeptical to try this because I am in South Africa and we have limited choice of ingredients. Well, they cam out perfectly and I am so happy I made the effort, thank you! It was so easy to make and I will definitely make it again!”– Linda
“Wow! Easy and delicious ! I’m addicted! I don’t usually like the texture of mug cakes, but these are wonderful. Thanks again for another winner!”– Joan
Ingredients needed
- Peanut butter: I recommend a good natural peanut butter like Santa Cruz. But you can use any nut butter here if you are allergic to peanuts.
- Butter: I like to use salted butter because the salt brings out a little flavor. You can also use coconut oil if you want to be dairy-free.
- Almond flour: As always, the finer your almond flour, the better the texture of your cakes. I have been using Blue Diamond lately and find it works quite well.
- Sweetener: Use your favorite granular sweetener. I really like the flavor that Swerve Brown adds here, but you can also use allulose or BochaSweet.
- Dark chocolate chips: Both ChocZero or Lily’s work nicely in this mug cake recipe. You can also skip the chips to save on a few carbs, if you like.
- Kitchen staples: Eggs, baking powder, and vanilla extract.
Step-by-step directions
1. In a microwave safe bowl, melt the peanut butter and butter together in short bursts, stirring until smooth.
2. In a medium bowl, whisk together the almond flour, sweetener, and baking powder.
3. Stir in the eggs, vanilla extract, peanut butter mixture, and water until well combined. Stir in the chocolate chips.
4. Divide among 6 ramekins or mugs and microwave each for about 1 minute, until puffed and set. Serve warm.
Expert tips
Peanut butter tends to thicken cake batters the longer it sits, so you need to work relatively quickly on this one. Try to get it into the mugs as soon as it’s all mixed together and then cook them straight away.
Several readers have asked if they can prepare the batter and then refrigerate the cakes until they are ready to make them. This doesn’t work well because the batter can thicken and the cakes won’t rise properly. You are better off cooking all of the cakes and then re-warming it when you are ready to eat.
We like to eat them right out of the mugs but if you want to remove them, be sure to grease your mugs or ramekins very well.
Oven Baked Method: If you prefer to make these in your oven, try baking them at 350ºF for 12 to 15 minutes.
Nut-Free Version: You can make these with sunflower butter and sunflower seed flour. But you will want to replace 1 tbsp of the water with some lemon juice to offset the green reaction that occurs between sunflower seeds and baking powder.
Frequently Asked Questions
Cover extra mug cakes tightly and store at room temperature for 1 day. You can also store them in the refrigerator for up to 5 days. To reheat, place it in the microwave for 15-20 seconds until just warm.
You can also freeze extra mug cakes. Wrap them tightly in plastic wrap or foil and freeze for 3-6 months. If freezing, it is best to remove them from the mug first, then wrap and freeze.
This keto mug cake recipe has 6.7g of carbs and 3g of fiber per serving. That comes to 3.7g net carbs per mug cake.
More keto mug cake recipes
Peanut Butter Keto Mug Cake Recipe
Ingredients
- 1/3 cup (86 g) peanut butter
- 1/4 cup (56.75 g) butter
- 2/3 cup (157.73 g) almond flour
- 1/3 cup (60.67 g) Swerve Sweetener
- 2 tsp baking powder
- 2 large eggs
- 1/2 tsp vanilla extract
- 1/4 cup water
- 3 tbsp (45.65 g) dark chocolate chips, sugar-free
Instructions
- In a microwave safe bowl, melt the peanut butter and butter together in short bursts, stirring until smooth.
- In a medium bowl, whisk together the almond flour, sweetener, and baking powder.
- Stir in the eggs, vanilla extract, peanut butter mixture, and water until well combined. Stir in the chocolate chips.
- Divide among 6 ramekins or mugs and microwave each for about 1 minute, until puffed and set. Serve warm.
Notes
Nutrition
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I never had luck with mug cakes, but figured to try one last time. And I’m so glad I did! These are amazing, even picky husband likes them! Thanks for sharing it. 🙂
Happy to hear it!
This mug cake is the best that I’ve tried!
Could you substitute defatted peanut flour for the peanut butter. I don’t keep peanut butter on hand but do keep the peanut flour
You would have to reconsistute it with liquid first and I am not sure how much.
Thanks. I do keep PB2 so I could add the water to it first. I was thinking of using actual peanut flour but I bet the PB2 would work better.
I love that these are sugar free! It makes it easier for some of my friends to have treats that are sugar free!
My daughter is really going to love this! thanks for the recipe
You had me at Peanut Butter and mug cake!
I love mug cakes – and this one is SO delicious!
Peanut Butter and Chocolate plus low carb =‘s a huge win! A must try for sure.
Question: I have been loving this recipe as I refrigerate leftovers for quick breakfast next several mornings! I started the recipe this morning only to realize I’m out of Almond flour. Can I use THM baking blend? Would it be the same amount? Thanks!
It will probably be a bit more dry so add some butter.
Hi Carolyn
I love your website and recipes.
I noticed you use your microwave a lot and would like to ask if you can give the oven/cooking alternative in your recipes when you use the microwave? I do not have one for health reasons. Many thanks
I am sorry, but this is a microwave based recipe and I didn’t test it in the oven. I cannot give you an oven method if I didn’t test it that way…you will have to experiment on your own. However, if you read through the comments, others have already done so.
Recipe is missing; link appears broken.???
It’s not you. My site is having issues and we are trying to get it fixed ASAP
This is the best low carb dessert I have made yet! I put it all in a loaf pan, baked on 325 for 35 minutes. Next time I will raise the temp to 350, and check on it at about 20 minutes in. At 325, I kept having to add time. The whole family enjoyed this, thank you!
Loaf pan! Great idea!
For those wondering about how long to cook in the oven, I cooked them at 350° for 17 minutes in ramekins and they came out perfect. I also subbed almond butter for the peanut butter. Delicious!
OMG this was so good. I have neither a microwave nor an oven, so I ended up making this in a shallow bowl in my toaster oven, and while it didn’t quite rise properly (the toaster oven isn’t the greatest), it was still amazing. Thank you!
Love the taste of your deserts. I am having a problem with my cakes turning out crumbly & dry yet I use the brands you do. Any suggestions that I could use to maybe help?
Sounds like they are getting over-cooked. Do you use the same sweetener? Same brand of almond flour?
Very easy to make and a hit with my fussy daughter and husband. Yum!
I just made these and divided into four larger size coffee cups. All puffed up perfectly. I added a dollop of whipped cream that I added confectioner swerve, a 1/2 tsp of vanilla and a 1/2 tsp of hennessey for fun.
Can defatted peanut flour be used in place of peanut butter?
I don’t really know. Possibly if you make it into a peanut “butter” first?
This is sooo good! I doubled it and baked it at 325 for about 20 min. Forgot to set the timer so just kept adding time. My husband and I love it. Thanks!
I used about 1/2 c gentle sweet and a dash of stevia extract. Also natural peanut butter.
I have just another question please, what kind of peanut butter did you use in this was it sugar free? They really did turn out good and I am going to add just a little bit more sweetener I just don’t understand why it wasn’t that sweet to me I have been on this low carb way of eating for a year so it’s not like I am not used to eating no sugar. Thank you so much for this recipe will try to tweak it a little.