Low Carb Mug Brownie with Peanut Butter Swirl

Chocolate and peanut butter are a classic combination and there's no better way to enjoy it than in this peanut butter and brownie swirl mug cake with just 3.3 net carbs.
Prep Time 2 minutes
Cook Time 1 minute
Total Time 3 minutes
Servings 1 brownie mug cake
Author Marye


  • 1 tablespoon almond flour
  • 1 tablespoon chocolate whey protein powder
  • 1 tablespoon dark cocoa
  • 2 teaspoons sugar free sweetener
  • Pinch of kosher salt
  • 1 egg yolk
  • 2 tablespoons butter softened
  • 1/4 teaspoon vanilla extract
  • 2 tablespoons club soda
  • 1 tablespoon peanut butter divided use


  • Grease the mug with a light coating of butter.
  • Mix the almond flour, protein powder, cocoa, sweetener, and salt.
  • Add the egg yolk, butter, and vanilla.
  • Mix until smooth.
  • Stir in the club soda until well mixed.
  • Spoon into the mug.
  • Microwave the peanut butter 15 seconds.
  • Spoon 1-1/2 teaspoons of the peanut butter over the cake and swirl through the batter with a knife.
  • Microwave on high for 20 to 30 seconds, or until it is just firm on top. Don't overcook or it will be dry.
  • Remove from the microwave (some shrinkage is normal).
  • Drizzle with the remaining peanut butter.