How To Reheat A Casserole In the Oven

To reheat a frozen casserole:

You can reheat a frozen casserole in two ways; thawed or frozen. 

Frozen

• To reheat a frozen casserole from frozen you can place it directly into the oven (350 degrees F) if it has been frozen in an aluminum pan or if it has been transferred to a storage container. 
• If it is in a storage container, transfer it to a casserole dish to place in the oven. Do not place glass or stainless steel casserole dishes into a hot oven directly from the freezer.
• To test for doneness, use a knife and insert it into various parts of the casserole, feeling the knife afterward to see if it is hot.
• If it is, remove the casserole from the oven. If it is not hot after being inserted into the casserole bake for an additional few minutes, testing after 5-10 minutes so the casserole does not get dried out. 

Note: frozen casseroles will take much longer to reheat than thawed casseroles.

To reheat a pre-cooked casserole

• Remove the casserole from the fridge and let it come to room temperature. 
• Place the casserole, covered, in an oven preheated to 350 degrees. 
• Allow the casserole to reheat for about 20-30 minutes. The amount of time required will depend upon what it is you are reheating and how dense the casserole is. 
• To test for doneness, use a knife and insert it into various parts of the casserole, feeling the knife afterward to see if it is hot. If it is, remove the casserole from the oven. If it is not hot after being inserted into the casserole bake for an additional few minutes, testing after 5-10 minutes so the casserole does not get dried out.

Tips

• Make sure to cover your casserole when reheating it so it doesn’t lose any moisture. 
• Wait for the oven to preheat completely before placing the casserole inside. You want the casserole to reheat at the maximum heat for the least amount of time to minimize moisture loss. 
• Do not put a cold glass casserole or a cast iron dish into a hot oven as it may crack due to the extreme temperature change. 
• If you want your casserole to have a crispy top, remove the aluminum foil for the last 10 minutes of reheating or turn on the broiler for a few minutes to crisp it up. This also works for casseroles that are cheese-topped. 
• When covering a cheese-topped casserole make sure to spray the aluminum foil with cooking spray so the cheese does not stick. 
• If your casserole looks dry while it reheats, you have a few options, depending on the type of casserole it is you can:
  • Pour in chicken, beef, or vegetable broth.
  • Add milk, cream, or a touch of water. 
• Invest in an oven thermometer to ensure your casserole is heated through. It is safe to eat when it reaches 165°F.
• For faster reheating and to lower the risk of drying out the casserole, reheat just what you think you’ll eat so you don’t need to reheat the casserole a second time. 

Reheating Casseroles With Crispy Topping

• Casseroles featuring a crispy topping, like bread crumbs, french fried onions, or potato chips (e.g., old fashioned cabbage casserole or million dollar chicken), should be reheated with foil initially.
• After heating through, uncover, raise the oven temperature to 375ºF, and add extra topping for 5-10 minutes until it regains its crispiness.

Reheating Casseroles With Cheesy Topping

For casseroles with a cheesy topping, like chicken broccoli rice casserole, cover with foil before reheating.

• To prevent sticking, spray the foil with nonstick cooking spray.
• Once reheated, uncover and bake for an extra 5 minutes to achieve a golden, bubbly cheese.
• Consider adding more cheese for a delicious finish, reminiscent of the first serving!

Looking for casserole recipes?

• Cauliflower Salmon Casserole
• Breakfast Strata
• Creamy Corn Casserole
• Taco Casserole With Tortillas
• Lazy Cabbage Casserole With Ground Beef

For all baking recipes, hop on to our One-Pot Casserole collection.