Three-ingredient Peanut Butter Mug Cake

Not only does this delicious peanut butter mug cake only require three ingredients, it is also made in your microwave, making this the easiest bake you ever did make.

From the book

Three Ingredient Baking by
Three Ingredient Baking
100 inspired recipes using only three ingredients
Foolproof recipes for classic favourites
From indulgent desserts to guilt-free treats


Mug cakes are ideal if you don’t have time to whip up a proper cake – and you can normally make them from a few odds and ends in the back of the cupboard. For me they bring back the magic of baking: put everything in a mug, give it a stir – and pop it in until it pings!


140g (roughly 3 tbsp) crunchy peanut butter
30g granulated sugar
2 eggs

Essential kit

You will need: a suitable mug – a chunky ceramic one that can withstand the heat (you don’t want a cracked cup) and that won’t get too hot. Look on the base for one that’s microwave-proof.


Measure the peanut butter and sugar into the mug. Crack in the eggs, and whisk everything together using a fork. Once the batter is fully combined – it should go around three-quarters of the way up the mug – put it in the microwave and heat on high for 1 to 2 minutes.

In my 700W microwave (category D), it takes exactly 1 minute, 45 seconds – but don’t worry if yours is diff erent. Just watch through the glass so you can see the cake slowly rise around 2.5cm over the edge of the mug. It will sink a little as soon as the heat stops, but if it falls below the mug rim, blast it for another 5 to 10 seconds – it’s ready when it stays risen.

Use an oven glove or tea towel on the handle of the mug to take it out of the microwave. Let the cake cool for a minute before digging in.

Tip: Try cashew or almond butter instead of peanut, or you can even use chocolate hazelnut spread. If you’re feeling particularly indulgent, add another spoonful on top before eating – it will go all gooey as it starts to melt into the cake.

See more recipes »

More Cake Recipes

See more recipes »

More Microwave Recipes

See more recipes »

More Recipes from Three Ingredient Baking