Dessert

Peanut Butter Mug Cake Recipe

ByClara Bennett March 2, 2026March 2, 2026

Introduction

This Peanut Butter Mug Cake is a quick and delicious treat you can make in just minutes. Perfect for satisfying your sweet tooth without any fuss or oven time.

A clear glass mug sits on a stack of three white plates on a wooden tray, filled with a light brown, creamy mousse-like layer as the main base. On top, there is a thick layer of white whipped cream with a rough texture, sprinkled with crushed light brown nuts. Around the mug on the plates and tray, scattered whole nuts add texture and detail. The scene is set on a white marbled surface, with a soft beige cloth and a dark brown bottle with a yellow label in the background, and a vintage silver spoon placed beside the plates. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 ½ tbsp butter (melted)
1 ½ tbsp peanut butter
1 egg yolk
2 tbsp brown sugar
1 ½ tbsp milk
⅛ tsp vanilla extract (optional)
2 tbsp flour
⅛ tsp baking powder
a pinch of salt
vanilla frosting (optional)

Instructions

Step 1: Melt the butter directly in a microwave-safe mug. Add the peanut butter and stir until smooth and combined.
Step 2: Mix in the egg yolk, brown sugar, salt, milk, and vanilla extract (if using). Stir until everything is well incorporated.
Step 3: Add the flour and baking powder, then stir again until you have a smooth batter without lumps.
Step 4: Microwave on high for 60 seconds. The cake should rise but still be moist.
Step 5: Let the mug cake cool slightly, then top with vanilla frosting and crushed peanuts if desired. Enjoy warm.

Tips & Variations

For a vegan version, substitute the egg yolk with a flax egg and use dairy-free milk and butter alternatives.
Try adding a pinch of cinnamon or cocoa powder to change up the flavor.
If you prefer a less sweet cake, reduce the brown sugar slightly.
To add texture, mix in some chocolate chips or chopped nuts before microwaving.

Storage

This mug cake is best enjoyed fresh but can be stored in an airtight container in the refrigerator for up to 2 days. Reheat gently in the microwave for 15-20 seconds before eating to regain softness.

How to Serve

The image shows a clear glass cup filled with a two-layer dessert. The bottom layer is a thick, smooth, light brown pumpkin mousse, topped with a fluffy, white whipped cream layer sprinkled with chopped nuts. The cup is placed on a stack of three white plates, with some whole and chopped nuts scattered around the plates and on a carved wooden round board beneath. To the left of the dessert is an ornate silver teaspoon, and in the background, there is a dark brown bottle with a label and a beige cloth draped softly. The scene is set against a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use a whole egg instead of just the yolk?

Using a whole egg may change the texture of the cake, making it more dense and less rich. For best results, stick to just the yolk as the recipe suggests.