As convenient as a microwave is, there are some foods that just shouldn’t be reheated in the microwave. Because it’s often used to transform a frozen tray of food into a delicious dinner in just a few minutes, it usually uses to much heat for food that’s not frozen. It explains why your lasagna is usually dry on the outside and cold on the inside. While the microwave is great for steaming vegetables, it’s not a good idea to use it to reheat pasta, casseroles, mashed potatoes, or pizza. Check out this list of foods that shouldn’t be reheated in the microwave and learn how to heat up leftover properly.