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Easy 5-Minute Keto Lemon Mug Cake

Yields2 ServingsPrep Time3 minsCook Time2 minsTotal Time5 mins

This keto lemon mug cake is ready in only a few minutes and will leave you satisfied and satiated with only 3.1g net carbs per serving!

Easy Sugar Free Keto Lemon Mug Cake

 2 tbsp (0.5oz/16g) finely ground almond flour
 2 tbsp (0.5oz/16g) finely ground coconut flour
 2 tbsp (1oz/28g) granulated erythritol
 1 egg
 1 tbsp (15ml) unsweetened almond milk
 1 tbsp (15ml) melted butter or coconut oil
 1 tbsp (15ml) lemon juice
 1 drop lemon flavoring (optional)
 ½ tsp (gluten-free) baking powder
Optional: Lemon Icing
 2 tbsp (0.3oz/12g) powdered erythritol
 1 tbsp (15ml) heavy cream
 1 tsp (5ml) lemon juice

Add all of the ingredients except for the ingredients for the optional lemon icing into a middle-sized bowl.
Whisk until you get a smooth and chunk-free dough.


Grease your microwave-safe mug or ramekin with cooking oil that doesn't have a strong taste (I like to use coconut oil, butter or avocado oil).


Add your cake batter into your mug or ramekin (the mug should be at least double the size of the mixed ingredients).

Instructions: Microwave

Microwave for about 1-3 minutes.
(The cooking time in your microwave may vary heavily depending on what microwave and what settings you're using.)

A broad rule of thumb: Approx. 1 Minute at 1200 Watt and more like 2-3 minutes at <600 Watt.

If you don't know the Wattage power of your microwave I'd recommend baking your mug cake for a shorter time period (60 seconds) first and continue baking for a few more seconds if needed.
This will avoid that the mug cake dries out.
You can test if your mug cake is completely cooked by pricking the center with a toothpick - if it comes out "clean" it's ready!

Instructions: Oven

Preheat your oven to 350 degrees Fahrenheit (180°C).
Follow the same steps as above.
Bake your mug cake for about 10-15 minutes.
You can test if your mug cake is completely cooked by pricking the center with a toothpick - if it comes out "clean" it's ready!

(Optional) Prepare the Lemon Icing:

Mix the powdered erythritol, lemon juice, and heavy cream and pour it over the finished keto lemon mug cake.


Enjoy warm or cold, both options taste great!


Cover with plastic wrap and store for up to 2 days in your fridge.

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**(I try to be as accurate as possible with the nutrition information below, but values may vary because of natural occurring fluctuations and different products used.)

Nutrition Facts

Serving Size 1/2 mug cake

Servings 2

Amount Per Serving
Calories 171
% Daily Value *
Total Fat 12.7g20%
Total Carbohydrate 7.6g3%

Dietary Fiber 4.5g18%
Protein 8.9g18%

* Percent Daily Values are based on a 2,000 calorie diet. Your daily value may be higher or lower depending on your calorie needs.