Normally, a cake would take an hour or more to make in an oven, but with a microwave oven, you can make one in minutes! Microwave ovens use waves of energy called – you guessed it – microwaves to cook food quickly. The microwaves go into the food and make water molecules inside move around really fast. The movement creates heat which cooks the food. But the microwave is just one part of this scientific process. First, you need to mix up ingredients. Two of the ingredients are key to making a tasty mug cake! Baking powder will make your cake spongy because it produces gas bubbles that get trapped in the batter as it cooks. The egg will help your cake rise because it has proteins that create a strong structure. Without these ingredients, your cake will look like soup! Experiment with the other ingredients to customize your mug cake. What will you add to give it a whole new flavor?!