Begin by melting the butter in your microwave-safe mug. Heat it for about 20-30 seconds, or until it’s completely melted.
Add the white sugar to the melted butter and mix well until it’s fully combined.
Pour in the boiling or hot water and stir again until the mixture is smooth.
Next, add the cocoa powder to the mug. Stir until the cocoa is fully incorporated.
Sprinkle in the self-rising flour and mix until everything is well combined.
Break the dark or semi-sweet baking chocolate into small pieces and fold them into the batter.
Place the mug in the microwave and cook on high for about 40-60 seconds.
Carefully remove the mug from the microwave and let it cool for a minute or two. Then, dig in!
