If you love peanut butter, but the chocolate peanut butter mug cake was a little too rich for you, here’s another option. This is a high protein, high fat, low carb, and filling mug dessert that’s perfect for people who love peanut butter.
See how you can make this indulgent treat for yourself in minutes. Single serve mug cakes are a great way to avoid going back for seconds and derailing your diet plans.
Peanut Butter Cake in a Mug for One
This recipe in its entirety has 10.7 net carbs. Feel free to leave off the topping to decrease the carb count a bit. Make sure you use natural peanut butter with only 1-2 ingredients.
Choose a PB with only peanuts as the ingredients — at the most you want peanuts and salt. Do not use a sweetened keto peanut butter, as we are adding sweetener to this mug cake.
Peanut Butter Mug Cake Ingredients
Here’s what you need to make this mug dessert. The exact measurements are in the printable recipe card below.
- Almond flour
- Coconut flour
- Granular keto sweetener
- Baking powder
- Melted butter
- Peanut butter
- Low-carb milk substitute
- Egg, lightly beaten
- Vanilla extract
Peanut Butter Cake in a Mug Directions
In a microwave-safe mug or dish that’s at least 8 ounces, mix the almond flour, coconut flour, sweetener, and baking powder until well incorporated.
Add the melted butter, 1 tablespoon of the peanut butter, milk substitute, lightly beaten egg, and vanilla extract. Stir until smooth.
Microwave for one minute and thirty seconds or until the top is opaque and cooked through.
Top the cake with the remaining peanut butter and allow it to melt, or melt and drizzle over the top of the mug cake.
For an extra stunning presentation, sprinkle additional erythritol and peanuts to the top of the mug cake.
PB Microwave Cake Recipe Notes and FAQ
How to choose a keto peanut butter.
Look at the ingredients of a peanut butter before buying. The ingredients should say peanuts and maybe salt — that’s it. Do not use a sweetened peanut butter in this recipe since the ingredients call for more sweetener.
Please note that if you have pets you should avoid peanut butter sweetened with xylitol altogether as it is deadly to them.
Can I make this into a full-sized cake?
Making this recipe as a full cake is not tested. Part of the allure of mug cakes is that they are fast and single serve. The high fat and protein makes this cake very filling and satisfying with only a mug full.
Which mugs are the best to use for mug desserts?
You need to use microwave-safe mugs, that’s the most important thing. If you want them to look nice like in our images, use 8 ounce mugs or ramekins.
The chocolate whipped topping might be another delicious topping idea. Be sure to factor in the macros if you try it!
Share this recipe with your dessert loving family and friends!
Peanut butter cake in a mug that's low-carb. Cake and all of the topping is 10.7 net carbs.
- 3 Tablespoons almond flour
- 1 Tablespoon coconut flour
- 1 Tablespoon Erythritol, granular
- ½ teaspoon baking powder
- 2 Tablespoons melted butter
- 2 Tablespoons low carb peanut butter, divided
- 3 Tablespoons milk of choice
- 1 egg, beaten
- 1 teaspoon vanilla
- In an 8 ounce mug, mix the almond flour, coconut flour, erythritol, and baking powder until well incorporated.
- Add the melted butter, 1 Tablespoon of the peanut butter, milk, egg, and vanilla. Stir until smooth.
- Cook in the microwave for one minute and thirty seconds or until the top is opaque and cooked through.
- Top with remaining peanut butter and allow to melt, or melt and drizzle over the top of the mug cake.
Nutrition facts calculated using Carb Manager and are not guaranteed to be 100% accurate.
Main nutrition facts include the cake and the topping.
Cake and entire topping is 10.7 net carbs.
Skip the topping to save some carbs.
For an extra stunning presentation, you can top with additional erythritol and/or peanuts.
As an Amazon Associate and member of other affiliate programs, I earn from qualifying purchases.
Serving Size:1 mug cake
Amount Per Serving: Calories: 776Total Fat: 66.4gSaturated Fat: 20.9gCholesterol: 247.5mgCarbohydrates: 33.3gNet Carbohydrates: 10.7gFiber: 10.6gSugar: 5.6gSugar Alcohols: 12gProtein: 24.8g
Other Low-Carb Mug Desserts
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Let me know if you make this low-carb peanut butter mug cake!