Ingredients:
- 2 1/2 tbsp natural creamy unsalted peanut butter
- 2 1/2 tsp Natural Mate All Purpose Granular Stevia or sugar substitute of your choice equivalent to 1 tbsp + 2 tsp sugar
- 1 large egg
Directions:
In a microwave-safe mug that can hold at least 12 oz of liquid, add all ingredients. Mix with a whisk until batter is completely smooth and egg is fully incorporated with no egg streaks remaining. Your batter should look like melted peanut butter.
Cook in the microwave at full power for about 1 minute. I used a 1000 watt microwave. You may need to adjust cooking time and power if your microwave is a different wattage. Cake is best enjoyed warm.
Notes:
- To make the mug cake even fluffier, add 1/8 tsp baking powder to the batter. I don't recommend adding more than 1/8 tsp because it will make the cake rise too much and dry out the cake.
- For the sugar substitute, I used Natural Mate Stevia All Purpose Natural Sweetener*
- If you have a favorite keto friendly sugar substitute, it will likely work with this recipe. Just make sure you add the equivalent of 1 tbsp + 2 tsp of sugar.
- If you like your cake a little sweeter, you can add a little more sugar (up to 1 tbsp stevia or 2 tbsp sugar substitute equivalent), but your cake will not rise as much.
- The cake is best consumed warm. If you are not consuming it right away, make sure to keep it covered or in a sealed container because it can get dry quickly if it's just left unsealed.
- The batter needs to be well-mixed. If you have streaks of egg whites not mixed in, your cake will not cook properly.
- I use a 1000 watt microwave. If your microwave power is less or more, please adjust cooking time and/or cooking power accordingly.
- *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).
Estimated Nutrition Information does not include toppings or carbs from erythritol.
Nutrition Facts
3 Ingredient Keto Peanut Butter Mug Cake
Amount Per Serving (1 cake)
Calories 318 Calories from Fat 225
% Daily Value*
Fat 25g38%
Saturated Fat 4g25%
Cholesterol 210mg70%
Sodium 80mg3%
Potassium 337mg10%
Carbohydrates 9g3%
Fiber 3g13%
Sugar 1g1%
Protein 15g30%
Vitamin A 305IU6%
Calcium 52mg5%
Iron 1.7mg9%
Net Carbs 6g12%
* Percent Daily Values are based on a 2000 calorie diet.
You didn’t say to butter the inside of the mug?????
You don’t need to. The cake will pull away from the sides when it is done.
Can I use honey as a sweetener?
I have not tested with honey.
This is BY FAR the best and easiest mug cake I’ve ever made. It’s so delicious, I added a little bit of lilly’s Chocolate chips and a touch of baking powder. It was so delicious and moist, I don’t even know how it was as good as it is. Amazing.
So happy you like it!
Wow. This tastes even better than mug cakes that call for almond or coconut flour and the texure was so fluffy and satisfying. Thank you so much for the recipe! Delicious.
I’m so glad you like it so much!
Hmm tempted to try with the chunky peanut butter I have ?
It works with chunky too
It’s awesome with chunky!
Has anyone tried this with almond or macadamia nut butter?
I recently made an almond butter version https://kirbiecravings.com/3-ingredient-keto-almond-butter-mug-cake/
how big of a cake does this make?
it fills a 12 oz mug
I don’t usually comment on recipes but wow! The texture of this is so much better than most keto mug cakes and it tastes awesome. I wish I had some chocolate on hand to go in it as well. This will be on my rotation for sure
I’m so happy you enjoyed!
I’m gonna try with unsweetened cocoa powder!
What a delicious treat! I used chunky peanut butter and sf chocolate chips on top. The consistency and the taste were both spot on. The best thing was how easy it was to make. Thanks!
I’m so glad you enjoyed the recipe!
Oh my this was like a slice of Heaven!! I threw in some Lily’s chocolate chips and topped it with a sugar free caramel sauce and a spray of whipped cream!! I’m making this again!! Thanks for sharing it!!??
I’m so glad you enjoyed!
This is an awesome recipe. I’m always searching for good low carb recipes for when my sweet tooth kicks in. The only thing I I did differently was add a little bit of honey. The texture was great, and it wasn’t too eggy like most mug cake recipes tend to be. Thanks so much!
I’m so glad you enjoyed it!