90-Second Chocolate Mug Cake

This chocolate mug cake is ready in 90 seconds in a microwave of about 800 watts. Stir flour, cocoa, sugar, baking powder, milk and oil together in a large mug and microwave it. You get one serving of warm, soft cake, with no pan, no oven and nothing to wash but the mug.

What to do with a stronger or weaker microwave

Ninety seconds fits a microwave of about 800 watts, the most common home wattage. The wattage is usually printed on a label inside the door or on the back. In a 1,000-watt microwave or stronger, start at 70 seconds. At 700 watts or less, go to two minutes.

The cake is done when it has risen and the center looks dry and crumbles a little when touched. It's better to take it out early and add ten seconds than to leave it in too long. A mug cake that dried out in the microwave turns rubbery, and there's no fixing that afterward.

Why a large mug and not a small cup

While it heats, the cake rises to almost twice its volume, then sinks back once you take it out. In a small cup the batter spills onto the turntable. A mug of at least 12 oz (350 ml), filled halfway, leaves it room. After microwaving, wait a minute before eating: the cake keeps setting from the heat, and the mug itself gets very hot.

For a dairy-free cake, swap the milk for almond or soy milk and the result is nearly the same. When you need cake for a crowd, there's the chocolate sheet cake for 30 kids, and for a chocolate dessert with no heat at all, try the two-ingredient chocolate mousse.

The recipe

90-Second Chocolate Mug Cake

A single-serving chocolate cake mixed and cooked in a mug, 90 seconds in an 800-watt microwave.

• Servings 1 serving
• Prep 3 min
• Total 5 min

Print recipe

Ingredients

• 4 tbsp / 30 g all-purpose flour
• 2 tbsp / 12 g cocoa powder
• 3 tbsp / 38 g sugar
• 1/4 tsp / 1 g baking powder
• salt (a pinch)
• 4 tbsp / 60 ml milk (or plant milk for dairy-free)
• 2 tbsp / 30 ml vegetable oil
• 1 tbsp / 12 g chocolate chips (optional)

Instructions

1. In a mug that holds at least 12 oz (350 ml), stir together the flour, cocoa, sugar, baking powder and salt.

2. Add the milk and oil and stir into a smooth batter, with no flour left at the bottom of the mug.

3. Sprinkle the chocolate chips on top, if using.

4. Microwave for 90 seconds at about 800 watts, until the cake rises and the center looks dry. In a 1,000-watt microwave or stronger, start at 70 seconds.

5. Wait a minute before eating, since the mug gets very hot.

Frequently Asked Questions

Why is my mug cake rubbery?
It stayed in the microwave too long. In a strong microwave cut the time to 70 seconds, and take the cake out once the center looks dry, even if it's still very soft.

Can I make a dairy-free chocolate mug cake?
Yes. Use plant milk instead of milk and check that your chocolate chips are dairy-free. There's no egg or butter in the recipe, so that's the only change.

What kind of mug works for a mug cake?
A microwave-safe ceramic or glass mug that holds at least 12 oz (350 ml). Not a mug with metallic trim.

Can I make two mug cakes at once?
Better one after the other. Two mugs heat more slowly and unevenly, and it's hard to tell when each one is done.