Add the butter to the mug and microwave for 35 seconds to melt.
Add the remaining ingredients to the mug and mix well with a fork.
Place the mug in the microwave and cook for 50 seconds, then check it. The cake should start to pull away from the sides and the top should look set, with the center still a little soft. If the center still looks shiny, microwave in 10-second bursts until it’s just set. Don’t wait until it looks dry, or it will taste dry.
Let the cake cool for about 5 minutes before eating.
Video
Notes
Choose the Right Mug or Ramekin: Use a mug that can hold at least 2 cups of water to prevent overflow and leave space for toppings. If you don’t have a mug, a large ramekin works just as well.
Mix Thoroughly: Ensure all ingredients, especially the egg, are well combined for a smooth cake texture.
Avoid Overcooking: Start microwaving for 50 seconds, then check and add 10-second increments as needed to avoid a dry cake.
Add Your Twist: Customize with cinnamon, peanut butter drizzle, nuts, or caramel for extra flavor.