This easy keto peanut butter mug cake is a deliciously rich and satisfying dessert. It is ready in just 4 minutes.
This chocolate peanut butter mug cake tastes so good. It is packed with peanut flavor and it is gently sweet. It satisfies that peanut butter craving I often get.
I made the recipe several times before it was perfect.
First, I tried a flourless peanut butter mug cake with only 4 ingredients - peanut butter, egg, sweetener and baking powder. This tasted good, but the texture was a bit firm, especially once cooled.
To fluff it up, I added coconut flour and a good measure of heavy cream. These additions give the mug cake a fluffy yet satisfyingly moist crumb. It's like a decadent mini version of my keto peanut butter bread.
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Why This Recipe Works
Quick. This mug cake cooks in the microwave in just 90 seconds. The total time to make the recipe from scratch is 4 minutes. We can all wait 4 minutes for dessert!
Low in carbs. One serving is only 3.6 grams of net carbs. The cake is also naturally gluten-free.
Lovely texture. Not eggy or weirdly spongy like so many keto mug cakes. This one tastes like cake.
Doubles up as breakfast. If you leave out the chocolate chips and use almond milk in place of the cream, you've got a delicious, healthy peanut butter mug cake to start the day.
Ingredients
Let's take a closer look at the ingredients for this keto peanut butter mug cake recipe.
- Peanut Butter - I used smooth peanut butter by Meridian, which only contains one ingredient - peanuts. Make sure your peanut butter is soft and creamy. Also, be aware that not all peanut butter is keto-friendly. Always read the ingredients when you shop. Some brands add sugar or inflammatory vegetable oils.
- Egg - You need a medium egg for this recipe.
- Coconut Flour - Sifted
- Sweetener - I used powdered erythritol. You can also use allulose, Bocha Sweet, monk fruit sweetener or stevia. Even granulated sweeteners will work well in the recipe. Mug cakes are forgiving.
- Heavy Cream - Adds moisture
- Baking Powder - To help the cake rise
- Chocolate - Optional. I used chopped 90% dark chocolate by Lindt. You can also use sugar free chocolate chips.
Instructions
This section contains step-by-step instructions and photos that show how to make this recipe. See the recipe card for full information on ingredients and quantities
Keto mug cakes are simple, and this one is no exception. Here are the basic steps:
1.) Put all ingredients into a mug.
2.) Mix the ingredients with a fork inside the cup.
3.) Stir in the chopped chocolate.
4.) Microwave until the cake is cooked and starts to peel away from the mug.
Enjoy as is or top with sugar free whipped cream, peanuts and shaved chocolate.
Katrin's Top Tips
#1 Choose a tall vessel for microwaving. You want to have at least 3 fingers space at the top. Mug cakes rise as they cook. You don't want the batter to spill over the top.
#2 Microwaves have different power levels and some cook quicker than others. Pause the microwave to check after about 50 seconds. If necessary, continue cooking the cake in 10-second bursts, up to 90 seconds in total.
This cooking method will also prevent spillage as you’re giving the cake time to sink back down in between.
#3 The cake tastes best when it is warm.
Variations
Most of the time, I make this recipe exactly as written. But sometimes I experiment with the flavor and with the ingredients. Here are a few ideas:
- Possible add-ons for are ½ teaspoon vanilla extract or 1 teaspoon cinnamon.
- To make this mug cake dairy-free, use coconut cream in place of the double/heavy cream.
- If you prefer cakes with almond flour, use ¼ cup or 4 ½ tablespoons of almond flour instead of coconut flour.
- Ran out of peanut butter? You can use almond butter or any other nut butter in this recipe.
Recipe FAQs
Yes. If you do not have a microwave, simply cook the mug cake in the oven. Use oven-proof ramekins and bake at 180 Celsius (350 Fahrenheit) for around 10 to 12 minutes.
You can use almond milk or another nut milk in place of the heavy cream.
There are 2 servings in the recipe. I made 1 cake to share. 2. If you don’t want to spoon from the same cup, simply divide the mix between 2 ramekins. The cooking time remains the same.
Storage And Reheating
Store leftovers in the fridge for up to 3 days. You can also freeze the cake for up to 3 months.
If you divide the batter between 2 ramekins and eat one cake straight away and one the next day, I recommend that you refrigerate the second portion as a batter. Then, cook it straight before eating.
It is also possible to gently re-warm a cooled cake in the microwave for around 10 seconds.
More Keto Mug Cake Recipes
- Keto Vanilla Mug Cake4 Minutes
- Keto Mug Cheesecake (Microwave Recipe)8 Minutes
- Fudgy Keto Brownie In A Mug3 Minutes
- Keto Blueberry Mug Cake4 Minutes
Tried this recipe? Give it a star rating below!
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Recipe
Keto Peanut Butter Mug Cake
from Sugar Free LondonerNote: The servings slider only changes the first amount in each line and not any subsequent amounts. Please make your own calculations where necessary.
Ingredients
- 2 tablespoon peanut butter soft
- 1 ½ tablespoon coconut flour
- 1 ½ tablespoon powdered sweetener add an additional ½ teaspoon if you have a sweet tooth
- 3 tablespoon heavy cream or coconut cream for dairy free
- 1 egg medium
- ¼ teaspoon baking powder
- 1 tbsp dark chocolate, chopped or sugar free chocolate chips optional
Instructions
- Mix all ingredients in a tall glass or mug, using a fork. Fold in the chocolate last, if using.
- Microwave on high for up to 90 seconds. Check after 50 seconds and continue with 10-second bursts until the cake peels away from the mug and the centre is cooked.
Lionel Velez Jr
Can you make it with almond flour?
Katrin Nürnberger
It should work with around 4 tablespoons of almond flour.
Stella
Very yummy! I used a little over half of the called for sugar, used coconut cream and added the vanilla extract as well as 1 tbsp of Reece peanut butter chips and 1.5 tbsp of dark chocolate chips. This was so rich, I think I could have used even less powdered sugar. Definitely enough to share.
Claire McDonnell
Just made this. Best mug cake recipe I’ve made.
Kim
Yummy
Amy
Also I forgot to mention in my previous comment I did add the 1/2 teaspoon of vanilla extract. And I used a kitchen scale to measure 10 grams of coconut flour because that's more accurate than 1 1/2 Tablespoons. I think it makes a big difference how much coconut flour you add because it's so absorbent.
Amy
Fantastic recipe! SO delicious. I was looking for something more savory, not a dessert, so I omitted the sweetener and the chocolate chips. I substituted 3 Tablespoons skim milk for the heavy cream because that's what I had in the house. (I am not on the keto diet, just grain free). And I mixed the dry ingredients separately from the wet, then mixed them all together and waited about 2 minutes for the coconut flour to absorb more liquid. I cooked it for 90 seconds in a 2 cup (500 ml) glass measuring cup to make sure it didn't overflow. With my modifications, it tasted more like peanut butter bread which was exactly what I was looking for. The texture is AMAZING. It is not greasy nor too eggy like other coconut flour mug cake recipes I've found online. Thank you thank you thank you! This is the first recipe I've tried from your website and now I'm going to try more.
t. saunders
Very easy! One of the best tasting Keto mug cakes! I added sugarless chocolate chips and pecans… so so yummy
nina
Can this cook in the oven or the air fryer?
Katrin Nürnberger
Yes, I would go for 180 C electric / 160C fan and about 12 minutes. Then test if it's done.
Derek
I found this recipe by searching specifically for recipes that only use coconut flour instead of almond flour, since it's so much cheaper than almond flour. It was really good. And....Although my pet peeve is when people leave comments talking about all the ways they modified the recipe instead of just reviewing it as written, I am doing it myself today simply because the result was so excellent when I changed it.
2 Tbsp coconut flour
1/2 tsp baking powder
2 Tbsp peanut butter
1 Tbsp granular sweetener
3 Tbsp peanut butter
1 egg
3 Tbsp Almond Milk
Mix, pour into bowl, microwave for 99 seconds. I love this. Coconut flour is so much cheaper than almond flour, and almond milk so much cheaper than heavy cream.
Viv
You have noted panut butter twice in your recipe 2 Tbsp and 3 Tsp? Is this correct
Onthego Mom
I don't have Coconut or Almond flour, will this work with Regular flour, I'm not on a keto plan so if it'll work, I'll try it???
Katrin Nürnberger
It would be a similar amount to almond flour. Maybe a bit less. You'd have to experiment.
Jacqueline
Can I substitute coconut cream with coconut butter or plain Greek yoghurt?
Katrin Nürnberger
I would try greek yoghurt, that should work.
Marie
Hi Katrin I have seen in one of your comments somewhere a place in UK where you get your keto baking items etc..
Just wondering would you post it again here.
Looking forward to trying this mug cake .
Thanks