Chocolate Peanut Butter Mug Cake
Chocolate Peanut Butter Mug Cake
This single-serving cake uses Greek yogurt, egg, cocoa, and powdered peanut butter in a 12-ounce mug. Microwave power varies, so the method uses short increments and a 160°F egg-safe endpoint instead of relying on one universal time.
Details
- Yield: 1 mug cake
- Prep: 5 minutes
- Cook: about 60–100 seconds in a 1000-watt microwave
- Equipment: 12-ounce straight-sided microwave-safe mug, bowl, whisk, spatula, thermometer
Ingredients
- 1 large egg
- 1/4 cup plain Greek yogurt
- 3 tablespoons (18 grams) powdered peanut butter
- 1 tablespoon granulated sugar
- 1 tablespoon natural unsweetened cocoa powder
- 1/2 teaspoon baking powder
- 1/4 teaspoon vanilla extract
- Pinch of fine salt
- Cooking spray
Method
- Coat the inside of the mug lightly with spray. Set it on a microwave-safe plate.
- In a separate bowl, whisk egg and yogurt until no egg-white strands remain. Whisk in powdered peanut butter, sugar, cocoa, baking powder, vanilla, and salt until smooth.
- Scrape batter into the mug; it should fill no more than halfway.
- Microwave on high for 60 seconds. Check the center, then continue in 10-second increments until risen, no liquid batter remains, and the center reaches at least 160°F.
- Rest 2 minutes. The mug and steam will be hot; eat with a spoon rather than turning out immediately.
How the formula works
The egg supplies structure, yogurt keeps the small cake moist, and powdered peanut butter adds flavor while absorbing liquid. Cocoa also absorbs moisture, so level measurements matter. Baking powder creates lift quickly in the microwave. A narrow mug can overflow; the 12-ounce capacity and half-full limit leave space for expansion.
Troubleshooting
A rubbery cake was cooked too long or at unusually high wattage. Use shorter increments after the first minute. A wet center needs additional cooking even if the top looks set. Insert the thermometer into the center without touching the mug. Dry powder pockets mean the bowl was not scraped before transfer.
Substitutions and serving
Honey can replace sugar, but reduce yogurt by 1 teaspoon to offset added liquid. Dutch-process cocoa gives a darker flavor but may reduce rise slightly. Different powdered peanut-butter brands absorb differently; weigh 18 grams. Conventional peanut butter is not a direct substitution. Serve plain or with berries after the safety check.
Storage and allergen note
Mug cake is best freshly cooked. If necessary, cool and refrigerate within 2 hours for up to 2 days, then reheat to 165°F. Do not store it in a cracked or non-food-safe decorative mug. The recipe contains egg, dairy, and peanuts; verify labels and prevent cross-contact.
Microwave setup
Place the mug near the outer edge of the turntable rather than in the exact center, unless the appliance manual directs otherwise. The plate catches any accidental rise and makes the hot mug easier to remove. Use oven mitts and keep the face away when checking because trapped steam can escape from the center.
For microwaves below 900 watts, expect additional 10-second increments. Never compensate with one long uninterrupted cook, which can toughen the edges before the middle sets.
