1In a microwave-safe mug, combine the all-purpose flour, granulated sugar, cocoa powder, and baking powder.
Add the milk, vegetable oil, and vanilla extract to the dry ingredients.
Stir the mixture until smooth and well combined.
Microwave the mug on high for about 1 minute and 30 seconds, or until the cake has risen and is cooked through.
Allow the mug cake to cool slightly before enjoying.