3-Ingredient Flourless Peanut Butter Mug Cake

This peanut butter mug cake is my new favorite healthy snack! This mug cake recipe only has 3-ingredients, and is a keto mug cake too! Enjoy this easy peanut butter cake for breakfast, a snack, or quick and healthy dessert!

We eat peanut butter by the spoonful over here, so I’m surprised I haven’t tried a peanut butter mug cake before but today that changes!

I make this single serving banana bread all the time, and after trying this peanut butter mug cake, I know it will be in our regular rotation.

If you’d like to try a non-sweet recipe, you gotta try this 90-second Keto mug bread – it’s SO good!!

For other amazing 3-ingredient recipes, try this Nutella mug cake or 3-ingredient banana mug cake.

You might also want to try this chocolate peanut butter mug cake – it tastes just like a chocolate peanut butter cup!

What You Need to Make a Peanut Butter Mug Cake

No fancy equipment needed here! A microwave, measuring spoon, and a mug – that’s it. You don’t even need any measuring cups.

After starting Best Mug Cakes, I treated myself to a couple new cute mugs (this one, and this one). And I have this adorable mug added to my wish list, but I think I have to wait until a mug breaks because we don’t have any more room where we keep our mugs!

What are the 3 Ingredients in this Peanut Butter Snack Cake?

Well for starters, peanut butter.

An egg.

And granulated sugar, any kind you like.

I am a smooth peanut butter gal through-and-through so that’s what I use in this recipe. I think this pb mug cake tastes a lot yummier with the smooth cake texture.

But you chunky peanut butter folks out there feel free to substitute your favorite chunky peanut butter and crunch away to your heart’s content. This mug cake will still be super delicious. 🙂

I have tried making this mug cake recipe with drippy peanut butter and creamy peanut butter and it’s delicious and works well with both. Use whatever you have in your home.

If you want to keep this peanut butter mug cake keto, use erythritol or xylitol for the sugar, or any other of your favorite keto sweeteners (just make sure it’s granulated).

>> If you have a hankering for keto mug cakes, try this keto pumpkin mug cake too – it’s so good!! >>

Also check out this keto almond flour mug cake – it’s SO good and healthy too.

Otherwise, use whatever granulated sugar you like best. I usually use coconut sugar because I like the flavor (it doesn’t taste like coconut, it’s more like a brown sugar flavor).

Another yummy flourless mug cake recipe: Vegan Banana Bread in a Mug

How to Make a Peanut Butter Mug Cake

Crack the egg into a small bowl.

Add peanut butter and sugar and stir everything together well.

Pour the batter into a mug sprayed with oil.

Microwave for a minute and you’re done! It’s truly the easiest baking recipe.

Tips for Making this Peanut Butter Mug Cake

Make sure you stir the ingredients together well. If you don’t, you might end up with an eggy bite where the egg hasn’t mixed with the peanut butter. I think it still tastes delicious but that might not be for everyone, so mix it well.

Everyone likes different levels of sweetness in their baked goods. I prefer this peanut butter mug cake with ½ a tablespoon of sugar, but my other testers (husband and daughter) preferred the mug cake with 1 tablespoon of sugar. Try it out to see what you like!

Your peanut butter microwave mug cake might need slightly different cooking time than mine. Different microwaves and different size mugs will mean you might need to add a bit more time to be the perfect level of doneness. Mine was perfectly cooked at 1 minute. If you’re adding on a bit more time, make sure to watch it cook, and try adding 15 second intervals. I also put a paper towel under the mug in the microwave to catch any spills.

Top your peanut butter cake with a drizzle of peanut butter, with ice cream, chocolate chips, or all of the above!!

Let’s make this mug cake!

Now head on over and check out this 3-ingredient mug cake (it’s chocolate and flourless!!)

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Let me know what you think if you try this healthy peanut butter mug cake!