Chocolate Peanut Butter Mug Cake
Looking for a single serve cake you can make in under 2 minutes? This Chocolate Peanut Butter Mug Cake is a quick chocolate cake with a hidden peanut butter cup center.
Since I’m a small batch recipe and dessert for two blog, you’ve been asking for a single mug cake recipe.
What better time to introduce this Chocolate Peanut Butter Mug Cake than right before Valentine’s Day weekend?
You can make it as a single serving dessert or double it to share with your sweetheart.
It’s taken me this long to publish one because I’ve made my fair share of mug cakes in the past and haven’t been impressed.
If this recipe does well, I’ll make other flavors. Make sure you leave a review and comment if you make it!
So why is mine any better?
Not only did I test the batter multiple times to make sure it was perfect, I noticed some recipes didn’t have salt. One recipe didn’t even have vanilla!
Salt and vanilla are flavor enhancers that take your chocolate cake from fine to great.
If you’re wondering what that means exactly, make this single serve cake without them then make a second one with them. I guarantee you’ll taste the difference.
It can even be a fun science experiment for kids or beginner bakers.
To take my chocolate peanut butter mug cake over the top, I included a surprise peanut butter cup in the middle to make it extra chocolately and moist.
Plus I made sure to include details in my recipe about microwave watts and time so you don’t accidentally overcook your chocolate peanut butter mug cake.
Nothing is sadder than throwing out a cake you can’t eat then still having to do the dishes afterwards.
What is a mug cake?
As the name implies, you make a single serve cake in a coffee mug then microwave it for 1-2 minutes until done. Sounds easy enough!
Now let me be clear – it will never be a true replacement for an oven baked small chocolate cake. The texture will different, especially since it’s eggless.
But as long as you understand that, my chocolate peanut butter mug cake is a delicious dessert for those evenings where you want something sweet but it’s too late to bake.
Or perhaps you only have access to a microwave and are tired of making my Microwave Chocolate Chip Cookie. Maybe you’re in college or in a home with limited appliances.
Whatever the reason, this cake for one has a place at the dessert table.
What size mug do I need for a mug cake?
The biggest challenge for making a mug cake is figuring out what size mug to use.
For my chocolate peanut butter mug cake, you will need a 12 ounce standard mug (affiliate link), one you would find at Walmart or Target.
I tested my mug cake recipe in several types of mugs. You don’t want to go smaller than 12 ounces because the cake will rise and overflow.
However, you can go a bit bigger and wider but your cooking time will vary. That’s why I recommend checking it at 60 seconds then going another 15-30 seconds if it’s not done.
Don’t know what size mug you have? Fill it to the top with water then transfer the water to a measuring cup. That will tell you how many ounces your mug will hold.
How To Make A Chocolate Peanut Butter Mug Cake
Making the batter for your chocolate peanut butter mug cake is super easy! All you do is whisk then cook.
I usually make my batter in a separate bowl so I have more room to stir. However, if your mug is large enough you can make it directly in your cup.
First, whisk together your flour, cocoa powder, sugar, baking powder, and salt. Next, stir in the milk, melted butter, peanut butter, and vanilla until smooth.
Transfer the cake batter to your mug, adding a peanut butter cup just underneath the surface for an extra surprise.
Microwave for 60-90 seconds, let cool for 5 minutes, then eat!
How do you know when a mug cake is cooked?
Because microwaves and mugs vary so much, it’s hard to give you an exact cooking time.
I do know it won’t be done under 60 seconds unless you have a super duper industrial microwave or something.
For reference, I have a 700 watt microwave that’s maybe 5 years old and it was done after 75 seconds.
Check your mug cake after 60 seconds. The top should look solid but still be slightly sticky. If the edges look too wet, put it back in for another 15 seconds then check again.
Just a side note – my chocolate peanut butter mug cake has a peanut butter cup in the center, so it will always look “too wet” from that. However, the batter itself shouldn’t be soupy.
And if you’re not sure, it’s better to undercook it and have a little extra chocolatey batter than overcook it and have a dry rubbery mess.
How To Serve Your Mug Cake
Although you can eat your chocolate peanut butter mug cake as is, I do find it to be a little rich from the peanut butter.
That’s why I like to balance it out with some vanilla bean ice cream or whipped cream on top.
Don’t want to make whipped cream? No worries! Wash your single serve cake down with a glass of milk.
More Single Serve Recipes
Enjoyed this cake for one? Here are more single serve dessert recipes:
- Single Serve Chocolate Chip Cookie
- Single Serving Sugar Cookie Recipe
- Single Serve Brownie (Microwavable)
- Thick Hot Chocolate for one
- Biscoff Mug Cake from Modest Munchies
For the full list, check out my Single Serving Desserts post.
- 1/4 cup all-purpose flour
- 2 tablespoons unsweetened cocoa powder
- 2 tablespoons granulated sugar
- 1/4 teaspoon baking powder
- 1/8 teaspoon salt, preferably kosher
- 1/4 cup whole milk, room temperature
- 2 tablespoons unsalted butter, melted
- 1 tablespoon smooth processed peanut butter
- 1/2 teaspoon vanilla extract
- 1 snack size peanut butter cup (or 1 tablespoon chocolate chips)
For Serving (Pick One)
- In a large bowl, whisk together the flour, cocoa powder, sugar, baking powder, and salt.
- Whisk in the milk, melted butter, peanut butter, and vanilla until smooth and moistened.
- Transfer the batter to a 12 ounce standard microwavable mug. Once you fill it 95% full, add the peanut butter cup and cover with enough batter so it's not sticking out.
- Microwave on high for 60 seconds then check your cake. The top should look solid but still be slightly sticky.
There will be some melted chocolate from the peanut butter cup. However, if the edges look too wet, put it back in for another 15 seconds then check again.
Do not overcook your cake! If you're still unsure if it's done, it's better to have it under and a little gooey than dry and rubbery.
- Cool for 5 minutes then serve with whipped cream or ice cream.
- This recipe is written for a 12 ounce standard coffee mug. The cake will rise to the top, so do not use anything smaller. However, you can go bigger but your cook time will vary. Check it after 60 seconds then cook another 15-30 seconds as needed.
- Because microwaves are different in watts and age, your cook time will vary. I used a 5-year-old 700 watt microwave and was done after 75 seconds.
- To double this recipe, double the ingredients but cook only one mug at a time.
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Recipe adapted from Table For Two