This chocolate lava mug cake has soft chocolate cake surrounding a warm center made with dark chocolate. It cooks in the microwave and makes one quick dessert.
In a large microwave-safe mug, whisk together 3 tablespoons granulated sugar, 30 g all-purpose flour, ¼ teaspoon kosher salt, ¼ teaspoon baking powder, and 2 tablespoons unsweetened cocoa powder until evenly combined.
Add 3 tablespoons whole milk, 3 tablespoons vegetable oil, 1 large egg, and ½ teaspoon vanilla extract. Whisk until completely smooth, with no dry pockets remaining at the bottom.
Press 4 squares of dark chocolate into the center of the batter. Keep them together and push them just below the surface.
Microwave the chocolate lava mug cake on high for 75–90 seconds. The surrounding cake should be fully set with no wet batter, while the chocolate center remains melted.
Let the mug cake rest for 30–45 seconds, then serve it warm from the mug.
Notes
Microwave timing: Microwave power varies, so begin checking at 75 seconds. Continue only until the cake surrounding the center is fully set.Mug choice: Use a large microwave-safe mug with enough empty space for the batter to rise without spilling.Molten center: Keep the chocolate squares together in the middle. Melted chocolate, not wet batter, creates the lava center.