Casseroles are the definition of simple and delicious comfort food, but you still need to take a bit of care to bake the best casserole possible. If your recipe calls for a certain prep step, you shouldn't just skip it and throw everything in the oven, especially if you're using certain types of meat that need to be drained after cooking.

If your recipe calls for pre-cooked meat, there are some kinds of meat that need to have their fat and juices drained off before they're added to the casserole, while others don't require this step. High-fat meats like ground beef, pork, sliced ham, and sausage need to be drained to prevent your casserole from turning greasy and watery.

On the other hand, lean poultry like ground turkey or chicken shouldn't be drained, since these meats need to retain a bit of fat to avoid drying out in the oven. Also, if you don't mix your meat into your casserole immediately after pre-cooking it, you need to store it in the fridge to prevent bacterial growth and foodborne illness.