Pick a microwave-safe mug that holds at least 12 ounces. A larger mug prevents overflowing as the cake rises.
If you want a softer cake, choose a wider mug. If you prefer a taller, fluffier cake, a narrower mug works best.
Add the flour, cocoa, sugar, salt, and baking powder directly to the mug. Stir with a fork until everything looks evenly combined.
Pour in the milk, oil, and vanilla. Stir until the batter looks smooth and glossy.
Scrape the bottom and sides so you don’t end up with dry pockets of flour.
If you’re using chocolate chips, peanut butter, or berries, fold them in gently or sprinkle on top. A small piece of chocolate pushed into the center melts into a molten core that tastes incredible.
Microwave on high for 60–80 seconds.
Start with 60 seconds, then check:If the top looks wet, add 10–15 more seconds. If it’s risen and looks set, it’s ready. Let the mug cake cool for one minute. nThis helps the texture settle and prevents burning your tongue.