Ingredients
Method
- Whisk dry flours, sweetener, baking powder, and salt in a microwave-safe mug.
- Stir in egg, melted butter, and vanilla until smooth.
- Mix cinnamon, butter, and erythritol. Spoon a ribbon into the batter and swirl with a toothpick.
- Microwave on high for 60 to 90 seconds until set. Let cool one minute before eating.