First, in a microwave-safe mug ( roughly 1 cup ( roughly 1 cup measurement) all purpose flour, sugar, cocoa powder, baking powder, and salt. Then give the dry ingredients a good mix. (here you can also use brown sugar instead of white to give the cake a nice gooey texture).
Then add in the milk, vanilla essence and oil. Mix all the ingredients until well incorporated. Finally mix in some milk chocolate chunks into the batter.
Now microwave for 1 minute. (here I've used a 1200w microwave, if yours is different then the timing may vary. If the microwave you have is less than 1200w, it may take you up to 1.5-2 minutes to make the cake).
Take it out of the microwave oven and let it cool for a couple of minutes.
Dust your cake with some icing sugar and drizzle it with some chocolate sauce or you can serve the cake with some whipped cream or vanilla ice cream. Enjoy!