This single-serving peanut butter cake is just 3 ingredients and very easy to make. This cake doesn’t require any flour or low carb flour alternatives. The batter takes less than five minutes to prepare and you don’t even need a mixer. This is an easy cake to make when you’re craving something sweet but don’t want to make a full cake.
single-serving peanut butter cake in a yellow ramekin.

If you’re looking for a quick and easy dessert, this is it. I love that it can be eaten warm and served with ice cream, sugar-free syrup, or whipped cream.

Ingredients

  • Egg
  • Peanut Butter
  • Erythritol

Substitutions

  • The egg provides the structure for this cake. I do not know of a substitute for the egg for this recipe.
  • This recipe uses creamy peanut butter. You can use either natural or regular unsweetened peanut butter. Peanut butter can be replaced with almond butter.
  • Erythritol can be substituted with Lankanto monkfruit sweetener or Swerve.

overhead shot of the cake.

Keto Peanut Butter Cake Texture And Flavor

This cake has a very tight crumb, similar to other flourless cakes. It has a strong peanut butter flavor but is not super sweet. It is a little plain to eat on its own, so I recommend serving it with toppings like whipped cream, ice cream, or sugar free syrup.
close-up shot of a spoon scooping some cake.

More Easy Keto Cakes

4 from 4 votes

3 Ingredient Peanut Butter Cake (Keto, Low Carb)

This single serving cake is so easy to make with just 3 ingredients. It can be served warm with your favorite toppings.
Servings: 1 cake
Prep Time: 5 minutes
Cook Time: 17 minutes
Total Time: 22 minutes
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Ingredients

  • 1 large egg
  • 2 tbsp (32 g) creamy peanut butter, unsweetened
  • 1.5 tbsp (18 g) erythritol granular

Instructions
 

  • Preheat oven to 350°F. Grease the interior of an 8 oz ramekin or similar sized baking dish.
  • Add egg to a medium bowl. Whisk egg vigorously with a whisk for one minute.
  • Add in peanut butter and erythritol. Whisk until completely incorporated and batter is smooth. Pour batter into prepared ramekin.
  • Bake cake for about 16-20 minutes or until cake has risen and when you apply light pressure on the surface it bounces back. Cake should rise above the ramekin during baking but will sink down and shrink once out of the oven. Let cake cool a few minutes before serving. If desired, plate cake in a smaller ramekin or plate. I plated mine in a smaller ramekin. Serve with your favorite toppings like ice cream, whipped cream or sugar-free syrup.

Notes

  • If you have questions regarding substitutions, please see substitutions section of the post.
  • This recipe can be made with natural or regular peanut butter. I used natural and found it easier to stir in.
  • The ramekin I used for baking is an 8 oz ramekin that is 3.75 inches wide.
  • I used So Nourished erythritol sweetener granular*
  • *This product link is an affiliate link. This means I earn a small commission from qualifying purchases.
  • If you are on a keto diet, please remember to look at net carbs and not just total carbs. The net carbs count excludes fiber and sugar alcohols (carbs from erythritol).
Serving: 1cake, Calories: 262kcal, Carbohydrates: 25g, Protein: 14g, Fat: 21g, Saturated Fat: 4g, Sodium: 71mg, Fiber: 3g, Sugar: 2g, sugar alcohol: 18g, NET CARBS: 4
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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