Place all the dry ingredients in a mug or a ramekin and combine well.
(I used caffeine-free chicory coffee powder) Add the egg, coconut oil and stevia (if used) and mix well using a fork.
Microwave on high for 70-90 seconds.
When done, you can optionally top the mug cake with whipped cream or creamed coconut milk.
Preheat the oven to 175 °C/ 350 °F and cook for about 12-15 minutes or until cooked in the centre.
Enjoy!