Choose a Mug: Select a microwave-safe mug with a capacity of at least 300ml (10oz) to allow for the cake to rise without overflowing.
Mix Dry Ingredients: In the mug, whisk together the all-purpose flour, granulated sugar, cocoa powder, baking powder, and a pinch of salt until well combined.
Add Wet Ingredients: Pour in the milk, vegetable oil, and vanilla extract. Stir everything together until you have a smooth batter. Make sure there are no lumps.
Optional Chocolate Chips: If you like, sprinkle the chocolate chips on top of the batter.
Microwave: Place the mug in the microwave and cook on high for about 1 minute and 30 seconds to 2 minutes. The exact cooking time may vary depending on your microwave's wattage, so keep an eye on it. The cake should rise and set but still be slightly moist.
Cool: Carefully remove the mug from the microwave (it will be hot) and let it cool for a minute or two.
Enjoy: Dig in with a spoon while it's still warm! You can eat it directly from the mug or transfer it to a plate.Remember that microwave cooking times can vary, so you may need to adjust the cooking time slightly to suit your microwave's power. Enjoy your delicious chocolate mug cake!