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photo of a keto peanut butter mug cake
4.50 from 18 votes

3 Ingredient Keto Peanut Butter Mug Cake

This easy microwave mug cake is just 3 ingredients! It's so quick, easy and is also keto and low carb.
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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

Instructions
 

  • 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.
Serving: 1cake, Calories: 318kcal, Carbohydrates: 9g, Protein: 15g, Fat: 25g, Saturated Fat: 4g, Sodium: 80mg, Fiber: 3g, Sugar: 1g, NET CARBS: 6
The nutrition information provided are only estimates based on an online nutritional calculator. This is not a comprehensive list of all the nutrients in the recipe (i.e., does not include vitamins, cholesterol, etc). I am not a certified nutritionist. Please consult a nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.
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