This Chocolate Peanut Butter Mug Cake is moist, rich and indulgent. The chocolate cake is made from dark chocolate (no cocoa powder here!), with a generous dollop of smooth peanut butter.
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Hi guys! Did you have a nice weekend?
I had a nice relaxing weekend for once, that was until I realised I hadn’t created my new #MugCakeMonday post. Then it was a mad dash to get brainstorming for a new delicious mug cake for y’all today.
Good thing mug cakes are so darn quick and easy to make, eh?
I can’t believe we’re already on week 3 out of 4 for Mug Cake Mondays too. It’s kind of sad that next week will be the last instalment, and the fact that May will be almost over too. This year seems to be going at the speed of light!
How can it come to an end when I have so many ideas for future mug cakes, even seasonal ones like a Pina Colada mug cake? 😉
So I’ve decided to extend Mug Cake Monday throughout the remainder of the year! Whoop!
For the rest of the year, instead of Mug Cake Monday throughout May, I will be extending it to Mug Cake Monthly. On the first Monday of every month I will be posting a new mug cake (or cookie, oh yes).
If you fancy joining in the fun for #MugCakeMonthly, just holla’ me.
But today, for the pre-finale I bring you a chocolate peanut butter mug cake. This chocolate cake is made from decadent dark chocolate (no cocoa powder in sight here – just real chocolate, baby!) The batter is then topped with a generous dollop of peanut butter that oozes all the way down the core.
Overall, this chocolate peanut butter mug cake is moist, rich and super indulgent. This cake is so quick and easy to make this store cupboard ingredients too.
It’s waiting for you to dive your spoon in and find that gooey peanut butter core!

Chocolate Peanut Butter Mug Cake
Prep Time: 5 minutes
Cook Time: 1 minute
Yield: 1 mug cake
This Chocolate Peanut Butter Mug Cake is moist, rich and indulgent. A chocolate cake made with dark chocolate with a generous dollop of smooth peanut butter.
Ingredients:
- 2 tbsp unsalted butter
- 40g (1.4 oz) dark chocolate, finely chopped
- 1 medium egg
- 2 tbsp milk
- 3 tbsp granulated sugar
- pinch of salt
- 3 tbsp self-raising flour, see notes
- 2 tbsp peanut butter
- (optional) 1 tbsp salted peanuts, coarsely chopped
Directions:
- Add the butter and chocolate to a large microwave-safe mug and microwave in short 20-second bursts until melted.
- Add the egg and milk and beat with a fork until smooth.
- Add the sugar, salt and flour and beat again to smooth, microwave for 30 seconds then gently add the peanut butter to the top of the batter - do not stir.
- Microwave again for around 1 minute to 1 minute 10 seconds, or until cooked.
- (optional) top with more peanut butter or with peanut butter and peanut sprinkled on top.
Notes:
If you don't have any self-raising flour, substitute for plain (all-purpose) flour and add an additional ¼ tsp baking powder.
Feel free to play around with the recipe. Here are some examples of adaptations:
- If you want a more chocolate-y flavour, remove 1 tbsp of flour and add 1 tbsp of unsweetened cocoa powder.
- Again, to add more depth of flavour, add a pinch of instant espresso powder. If doesn't add a coffee flavour, just gives the chocolate flavour an incredible depth.

I’m participating in Mug Cake Monday during May with some other food bloggers. I will be posting a new Mug Cake recipe each Monday throughout the month of May.
Mary Frances from The Sweet-Tooth Life joined in this week with an awesome gluten and dairy free Caramel Swirled Peanut Butter Mug Cake. We both obviously have peanut butter on our brains this week! 🙂
What mug cake or mug cookie would you like to see next week for the ‘finale’?
Love Mug Cakes?
Chocolate Brownie Mug Cake – A brownie in a mug, in less than 5 minutes!
Honey Mug Cake – A sweet and sticky puddling-like cake with frosting.
Salted Caramel Mug Cake – An amazingly indulgent chocolate salted caramel cake, drizzled with salted caramel

This was so yummy! With a big dollop of peanut butter and some chocolate chips on top, I licked the mug clean!
I cook this for my girlfriend in the morning 🙂 and she was amazed, she loves me more than ever now 🙂 🙂 Thank you for sharing this amazing recipe with us.