Whisk all ingredients together with a fork inside a large mug.
Microwave for 1 1/2 minutes.
Top with your favorite low carb topping and enjoy.
Notes
Warning!! As tempting as it is to dive into a nice mug of warm chocolate cake, this cake really retains it's heat. So give this adequate time to cool down. Might be a good idea to stick it in the fridge for a bit before eating.