A good brownie should be rich, fudgy, and a little bit gooey in the middle. This keto brownie mug cake checks all of those boxes.
You only need a handful of simple ingredients and a microwave. The whole thing comes together in just a few minutes, which makes it perfect for those late night chocolate cravings.
And yes, it’s fully low carb and keto friendly. No regular flour, no sugar. Just real chocolate flavor without the carb load.
The melted butter and cocoa powder give it that deep, rich brownie taste. A sprinkle of flaky sea salt on top takes it to another level.
This is one of those recipes you’ll come back to again and again. It’s fast, it’s easy, and it honestly tastes too good to be keto.
Why You’ll Love This Recipe
Ready in Under 2 Minutes – This fudgy brownie mug cake goes from mixing to eating in about 2 minutes flat.
Intensely Fudgy and Rich – The egg yolk and melted butter create a dense gooey center that tastes like a real brownie.
Satisfies Chocolate Cravings Instantly – When a chocolate craving hits on keto this mug cake is the fastest way to crush it.
Recipe Ingredients
- 2 tbsp Almond Flour
- 2 tbsp Unsweetened Cocoa Powder
- 2 tbsp Granulated Erythritol
- 1 Large Egg Yolk
- 2 tbsp Melted Butter
- 1 tbsp Heavy Cream
- 1/2 tsp Vanilla Extract
- 1/4 tsp Baking Powder
- Pinch of Salt
- 1 tbsp Sugar-Free Chocolate Chips
- Flaky Sea Salt, for topping
How To Make
Step 1
In a microwave-safe mug (at least 12 oz), whisk together the almond flour, cocoa powder, granulated erythritol, baking powder, and salt until there are no lumps of cocoa remaining.
Step 2
Add the egg yolk, melted butter, heavy cream, and vanilla extract. Stir vigorously with a fork until the batter is completely smooth and glossy. The batter should look thick and fudgy, not cakey.
Step 3
Fold in the sugar-free chocolate chips, pressing a few down into the batter so they melt inside during cooking.
Step 4
Microwave on high for 50 to 60 seconds. The top should look barely set while the center still appears slightly underdone and jiggly. This is exactly what you want for that fudgy, molten texture.
Step 5
Let the mug cake rest for 1 full minute before eating. The residual heat will continue cooking it gently while keeping the center dense and gooey. Sprinkle with a pinch of flaky sea salt and enjoy immediately with a spoon straight from the mug.
Tips
Whisk the Dry Ingredients First
Cocoa powder loves to clump, especially when it hits liquid. If you don’t break up those clumps while it’s still dry, you’ll end up with little pockets of bitter cocoa powder in your finished cake.
Use a fork or a small whisk and really mix the almond flour, cocoa powder, erythritol, baking powder, and salt together before adding anything wet. Take an extra 20-30 seconds here. You want a completely uniform dry mix with zero lumps.
This small step makes a big difference in how smooth and fudgy the final texture turns out.
Use Only the Egg Yolk
This recipe calls for just the yolk, not the whole egg. The yolk is what gives this mug cake its rich, fudgy, brownie-like texture. If you add the whole egg (yolk plus white), the cake will puff up and turn cakey and spongy instead.
When you separate the egg, make sure no white sneaks in with the yolk. Even a small amount of egg white changes the texture more than you’d expect in such a small recipe.
Use a Large Enough Mug
A 12 oz mug is the minimum here. If your mug is too small, the batter can bubble up and overflow in the microwave, making a mess and leaving you with less cake.
The batter should only fill about one-third to halfway up the mug before cooking. If it’s higher than that, switch to a bigger mug. A wider mug also cooks more evenly than a tall narrow one.
More Recipes
- Keto 90-Second Chocolate Mug Cake
- Keto Brownies
- Keto Funfetti Mug Cake
- Low Carb Fudgy Brownie Bites
- Low Carb Red Velvet Mug Cake
Frequently Asked Questions
Can I use coconut flour instead of almond flour?
Coconut flour absorbs way more liquid than almond flour, so you cannot swap them at a 1:1 ratio. If you want to try it, use about 1 tablespoon of coconut flour instead of the 2 tablespoons of almond flour, and add an extra tablespoon of heavy cream to keep the batter moist.
That said, almond flour really is the best option here for achieving that dense, fudgy brownie texture. Coconut flour tends to make things more cakey, which is the opposite of what this recipe is going for.
Keto Fudgy Brownie Mug Cake
Ingredients
Method
- In a microwave-safe mug (at least 12 oz), whisk together the almond flour, cocoa powder, granulated erythritol, baking powder, and salt until there are no lumps of cocoa remaining.
- Add the egg yolk, melted butter, heavy cream, and vanilla extract. Stir vigorously with a fork until the batter is completely smooth and glossy. The batter should look thick and fudgy, not cakey.
- Fold in the sugar-free chocolate chips, pressing a few down into the batter so they melt inside during cooking.
- Microwave on high for 50 to 60 seconds. The top should look barely set while the center still appears slightly underdone and jiggly. This is exactly what you want for that fudgy, molten texture.
- Let the mug cake rest for 1 full minute before eating. The residual heat will continue cooking it gently while keeping the center dense and gooey. Sprinkle with a pinch of flaky sea salt and enjoy immediately with a spoon straight from the mug.