This easy keto lava mug cake has only 5 ingredients and cooks in 1 minute! It has a gooey molten chocolate centre and it's flourless, sugar free and naturally gluten-free. Only 4.4g net carbs.
I have a wonderful low carb keto lava cake recipe on my website that we make often. The gooey molten centre is just irresistible!
But what if you just want a molten lava cake quickly, without turning on the oven? Well, you need a microwave version!
This chocolate lava mug cake is the cheat's version of a proper lava cake.
Similar, but not the same! I love playing around with ingredients and creating new flavors and textures. Here's why you are going to love this easy low carb dessert:
🌟 Why You'll Love This Recipe
- It has a rich and deep chocolate flavor
- Soft and gooey texture with a molten chocolate centre
- You mix it with a fork
- Minimal washing up - batter is mixed directly in the mug
- Ready in 1 minute!
Microwaves cook cakes from the inside out. That's why I used a trick to achieve a molten center: I simply added a square of sugar-free chocolate into the middle of the batter.
During cooking, the chocolate melts!
Here are the ingredients you'll need:
- Egg - large
- Cocoa powder - You can use unsweetened cocoa powder, cacao powder or Dutch process cocoa for an extra dark chocolate flavour.
- Heavy cream - also called double cream.
- Powdered sweetener - I used powdered Bocha Sweet, but any powdered sweetener works. Erythritol, xylitol, allulose, monk fruit sweetener, Swerve - you choose.
- Sugar free chocolate - I chose a square (approximately 3x3 cm) of Planet Organic No Added Sugar chocolate, which is sweetened with erythritol. In the US, Lily's sugar free chocolate is an option. Alternatively, use a 90% dark chocolate such as Lindt.
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.
Step 1: In a mug or ramekin, blend together the egg and the cream with a fork.
Step 2: Add one tablespoon of cocoa powder and whisk until incorporated. Then add the second tablespoon of cocoa powder and blend until smooth.
Step 3: Now, stir in the powdered sweetener until no lumps remain.
Step 4: Place the square of dark chocolate on top of the batter. Alternatively, use sugar free chocolate chips.
Step 5: Microwave for about 1 minute until the mug cake starts to fold away from the edges and the chocolate square has melted.
Stick to the order in which I add the ingredients - it will make mixing much easier.
Enjoy the chocolate lava cake straight from the mug while it is hot. Alternatively, turn it out onto a plate and top with
- a dollop of sugar free whipped cream
- scoop of sugar free ice cream
- or a dusting of powdered sweetener
- sugar free chocolate syrup
To bake this cake in the oven, I'd go for 180 C / 350F (conventional) and around 9-11 minutes. This way, you'll get a "proper" molten center.
Make sure your microwave-safe mug or ramekin is wide rather than narrow. Don't fill it more than ⅔. You need 2 fingers of space between the batter and the rim. Mug cakes rise as they cook. You do not want the batter to overflow and make a mess.
Depending on the power of your microwave, timings are going to differ. My microwave cooks at 900 Watts and 70 seconds was perfect.
If your microwave cooks at 1000W or higher, 50-60 seconds will be enough.
At 800W and lower (medium powder), the mug cake should need around 80 seconds.
For an extra gooey cake, reduce the cooking time by 10 seconds. This means the sides will be soft and fudgy as well as the chocolate centre.
Chocolate lava filling tips
My chocolate square measured 3 x 3 centimetres. For a larger molten center, use 2 chocolate squares or 2 tablespoons of sugar free chocolate chips.
Two chocolate squares are likely to sink to the bottom of the batter. Therefore, consider placing them into the mug upright, leaning against each other like a pitched roof.
Alternatively, melt the chocolate separately and add it half way through cooking into the middle, once the batter has started to set.
More lava filling options: Sugar free white or milk chocolate, almond butter or peanut butter.
Since this is a single serve keto mug cake, I assume that you will eat it straight away.
It is possible to store it in the fridge for up to 3 days though. You could even freeze it for up to 3 months.
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Keto Chocolate Lava Mug Cakefrom Sugar Free Londoner
Note: The servings slider only changes the first amount in each line and not any subsequent amounts. Please make your own calculations where necessary.
- In a mug or ramekin, blend together the egg and the cream with a fork.
- Add one tablespoon of cocoa powder and whisk until incorporated. Then add the second tablespoon of cocoa powder and blend until smooth.
- Now, stir in the powdered sweetener until no lumps remain.
- Place the square of dark chocolate on top of the batter. Alternatively, use sugar free chocolate chips.
- Microwave for about 1 minute until the mug cake starts to fold away from the edges and the chocolate square has melted. Mine took 70 seconds (900W). Eat while warm.
- 800W: 80 seconds
- 900W: 70 seconds
- 1000W: 60 seconds