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Peanut Butter Keto Mug Cake - A Quick, Satisfying Low-Carb Treat

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Prep Time 5 minutes
Cook Time 2 minutes
Total Time 7 minutes
Servings: 1 servings
Ingredients Method

Ingredients
  

  • 2 tablespoons creamy, unsweetened peanut butter (natural, no added sugar)
  • 1 tablespoon unsalted butter (or coconut oil for dairy-free)
  • 1 large egg
  • 3 tablespoons fine almond flour (not almond meal)
  • 1 tablespoon granular erythritol or allulose (or preferred keto sweetener)
  • 1/2 teaspoon vanilla extract
  • 1/4 teaspoon baking powder (aluminum-free if possible)
  • Pinch of salt (optional, enhance peanut flavor)
  • 1–2 teaspoons unsweetened almond milk (as needed to thin the batter)
  • Optional toppings: sugar-free chocolate chips, a drizzle of heavy cream, whipped cream, crushed peanuts, or a sprinkle of cinnamon

Method
 

  1. Choose the right mug. Use a microwave-safe mug that holds at least 12 ounces to prevent overflow. A wider mug cooks more evenly than a tall, narrow one.
  2. Melt the base. Add the peanut butter and butter to the mug. Microwave for 15–25 seconds, just until soft and easily stirred. Whisk together with a fork until smooth.
  3. Whisk in wet ingredients. Add the egg and vanilla. Beat with the fork until fully combined and slightly frothy. This helps the cake rise and stay fluffy.
  4. Add dry ingredients. Stir in almond flour, sweetener, baking powder, and a pinch of salt. Mix until no dry pockets remain. If the batter looks very thick, add 1–2 teaspoons of almond milk to loosen it to a thick, pourable consistency.
  5. Optional add-ins. Fold in a teaspoon of sugar-free chocolate chips or a pinch of cinnamon for extra flavor.
  6. Microwave carefully. Cook on high for 45–60 seconds. Check the center; if it’s still glossy, microwave in 10-second bursts until set but slightly springy. Avoid overcooking or it will turn dry.
  7. Rest and enjoy. Let the mug cake sit for 1 minute to finish setting. Add toppings like a drizzle of cream or a dollop of whipped cream, then dig in warm.