This light and airy keto vanilla mug cake satisfies all urgent cake cravings! It's ready in just 4 minutes from start to finish and comes in at only 2.5g net carbs. We love it as a quick everyday sugar free dessert. With its fluffy crumb it is delicious as is, but I've included lots of ideas how to jazz it up in the post! Gluten free and low carb.

Baking proper cakes is lots of fun - if you have the time and energy for it. But some days I really just want to eat one portion of cake - quick. I don't want to turn on the oven, I don't want complicated prep, and I don't want 11 more slices tempting me over the next few days.
That's where mug cakes come in! This vanilla keto mug cake is so easy to make and just hits the spot. I love that you can stir it together with a fork. And that it cooks in just 80 seconds. It's an almost instant treat full of flavor!
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Ingredients
Here's what you need to make this easy low carb mug cake. I've included some substitution ideas.
- Almond flour - I'm using ground almonds. This is equivalent to regular almond flour in the US. Ground almond are coarser than super fine almond flour. If you want to use super-fine, reduce the amount to 1 ½ tbsp.
- Coconut flour - The mix of coconut and almond flour works really well in gluten-free, low carb recipes.
- Butter - You could replace this with coconut oil for a dairy free version.
- Egg - Use a medium egg if you can. I did try making this recipe with a large egg and found it a bit eggy.
- Sweetener - I used a granulated erythritol monk fruit sweetener blend that's a 1:1 sugar substitute. Allulose and xylitol would work as well. 1 tablespoon was just right for me, but if you prefer a sweeter cake add more.
- Baking powder and vanilla extract.
Best container for mug cakes
I've had my fair share of microwave mug cake accidents! If your mug, ramekin or dessert bowl is too small, the batter will overflow as it rises and make a mighty mess.
It's important that your vessel has a volume of at least 200 millilitres and is wider rather than narrow and tall. Mugs or ramekins should not be filled with batter more than half. Always, always have a few fingers of free space between the batter and the rim.
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.

Stir together the dry ingredients in a small bowl - almond flour, coconut flour, baking powder, sweetener. Take care to break up any lumps.

In a second bowl, whisk the egg using a fork. Then add the melted and cooled butter plus the vanilla extract and whisk until combined.
Add the dry ingredients to the wet and stir until a smooth batter forms.

Grease a mug or ramekin with butter and fill in the batter. Microwave for 80 seconds @ 900 Watts.
Enjoy straight from the mug or invert onto a plate. I served it with a dollop of sugar free whipped cream.

Baking times for different power levels
My microwave operates at 900 watts and my cake took 80 seconds to cook. Here's a quick overview of recommended baking times for this low carb vanilla mug cake recipe:
- 600W = low power. 100 seconds.
- 800W = 90 seconds.
- 900W = 80 seconds.
- 1000W = 70 seconds.
Check the cake 10 seconds before it's finished and see how it's getting on. If it's still undercooked, add increments of 10 seconds. Just keep in mind that cakes continue to cook in the hot cup after you take them out. So don't be tempted to overcook!
Oven Instructions
To make this recipe in the oven, bake at 180 C / 350F for 12-15 minutes.
Recipe Variations
Here is how you could jazz up this keto mug cake:
- Stir berries into the batter - blueberries, raspberries or chopped strawberries. Crushed nuts such as pecans or walnuts would also be great
- Add sugar free chocolate chips or chipped 90% chocolate
- Turn it into a Victoria sponge cake! Turn it out onto a plate, slice in half and add sugar free strawberry jam and whipping cream
- Top with a simple keto cream cheese frosting - 2 tablespoon cream cheese mixed with a splash of vanilla extract and 1 teaspoon powdered sweetener
- Add 1-2 teaspoon of cocoa powder for a chocolate version
- Slather it with Vegan Keto Caramel Sauce!
More mug cake recipes
Love quick & easy sugar free cakes? Me too! See my other mug cake recipes below. Simply click on the image titles to go straight to the post.





Triple Chocolate Mug Cake - A deliciously moist nut free keto chocolate mug cake studded with sugar free chocolate chips and topped with a creamy chocolate sauce.
Keto Peanut Butter Mug Cake - Sometimes only a moist, fluffy chocolate peanut butter mug cake will do! This is a super popular recipe.
Microwave Mug Cheesecake - The perfect sugar free dessert if you crave cheesecake but don't want to make a large cake.
Sugar Free Lemon Mug Cake - Big flavor, light texture and with a deliciously zingy lemon glaze.
Tried this recipe? Give it a star rating below!
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Recipe

Keto Vanilla 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.
Equipment
- Microwave
Ingredients
- 2 tablespoon almond flour use only 1 ½ if super-fine
- 1 tbsp coconut flour
- 1 tbsp butter melted
- 1 egg medium, room temperature
- 1 tbsp granulated sweetener
- 1 tsp vanilla extract
- ¼ tsp baking powder
Instructions
- Stir together the dry ingredients in a bowl - almond flour, coconut flour, baking powder, sweetener. Take care to break up any lumps.
- In a second bowl, whisk the egg using a fork. Then add the melted and cooled butter plus the vanilla extract and whisk until combined.
- Add the dry ingredients to the wet and stir until a smooth batter forms.
- Grease a mug or ramekin with butter and fill in the batter. Microwave for 80 seconds @ 900W. (Baking times for different power levels are included in the notes below).
- Enjoy straight from the mug or invert onto a plate.
Video
Notes
- 600W = low power. 100 seconds.Â
- 800W = 90 seconds.
- 900W = 80 seconds.Â
- 1000W = 70 seconds.Â
Nutrition
First published May 2021. Updated August 2022.
Elsy
What amount of coconut oil can I use to replace the butter in your recipes, specifically mug cake?
Katrin Nürnberger
Just replace it 1:1, that always works well.
Pamela
Many mug cakes are too dry. Not this vanilla mug cake! I had a sweet craving and made this mug cake topped with a dollop of sugar free whip cream. Moist and tasty. Hit the spot! I might try a matcha version next.
Hannah
I put the melted the butter in a silicon cup and then whisked in the egg and vinegar extract and then whisked in the dried ingredients. It popped out perfectly, and it eliminated a dish to wash. I also use lemon extract instead of vanilla and when it was done I squeezed the juice of half a lemon on top. It was excellent!
I'm thinking of mixing maybe 10 times the dry ingredients and converting it into a mug cake mix. Then every time I make it, I can mix up the flavors a little bit. I'm going to try it with olive oil instead of butter as well.
Katrin Nürnberger
That's a great idea!
Mia
I just made one of these as a yummy coffee cake by adding a crumble on top with brown sugar substitute, cinnamon and chopped pecans. Delicious for my Saturday morning treat!
Lisa P
Best mug cake I've had yet, ( And I've tried LOADS!) Added a few choc chips to mine... delicious!. I wondered if it might be possible to make this savory, adding some parmesan and grated cheddar maybe? ( obviously leaving out sweetener) and some crispy bacon! I might give it a try. Fantastic recipes on this website, Thank you 🙂 xxx
Sheila
I made the Keto Vanilla Mug cake last night. It was wonderful. Just perfect for me. I'm diabetic and looking for low carb options. I made it today but I'm doing something different so I hope this works out. I put holes in the cake and poured sugar free Jello in the ramekin until it was full. I have it in the fridge and plan on having it after dinner.. I hope it turns out okay.
Patricia
Simply delicious . I will definitely be making this over and over again! Light,fluffy and yet filling.i made a little cream cheese frosting on it sprinkled with a few walnuts then dust of cinnamon.. I'm chilling now cause I made 3 cakes. Tastes better when chilled..thanks much
Rachel Brettell
Oh wow! Once I had drizzled sugar free maple syrup on mine it was like a sponge pudding! This recipe is perfect, thank you so much!
Sheila
Loved it one of my favorite treats. Quick and easy to make.
Louise
Sat here devouring a vanilla mug cake with a Christmas twist...
I had a small amount of keto mincemeat leftover from Christmas mincepies and so decided to throw it into the vanilla cake mix.
I made X2 the quantity of vanilla cake above, except only 1 large egg, then about 4-6 tbsp of mincemeat.
Ohhh yummm!!
This was my first Sugar Free Londoner's recipe... I've tried a lot of reduced sugar / no sugar recipes over the years and most of them you can tell it's not the full shabang but this is now only the start of trying Sugar Free Londoner's recipes
Katrin Nürnberger
So glad you like the recipe and your tweak sounds truly delicious. Keep me posted on any other recipes you try from the website and be sure to sign up to my newsletter so you know when I publish a new recipe!
Mimi
I have to leave a comment because that recipe is so delicious and hit all the right spots as well as coming out perfectly on 1st try! I am 9 months pregnant and was fancying a sweet treat but just couldn’t face standing up to bake a proper cake (and the subsequent washing up). This is a life-saver for late pregnancy craving! Thank you so much!!!