How to Reheat Casserole
Leftover casseroles of any type.
The Short Answer
The best way to reheat casserole is in the oven. Oven at 350 degrees F covered with foil for 20-30 minutes (portions) or 40-50 minutes (full pan).
Reheating Methods
🔥 Oven
Temperature: 350°F
Time: 20–50 minutes
Cover with foil for even heating. Remove foil last 10 minutes for crispy top. Add liquid if dry.
📡 Microwave
Time: 3–5 minutes
2-minute intervals, stirring. Check center, which heats last.
Do not reheat uncovered the whole time. The top burns while the center stays cold.
Most casseroles are designed to be made ahead, which means they are designed to be reheated. The flavors typically improve overnight.
Frequently Asked Questions
Yes. Do not thaw. Bake at 350 degrees F covered for 60-90 minutes. The center should reach 165 degrees F.
The Bottom Line
The best way to reheat casserole is in the oven. The key to great reheated food is low-and-slow heat, moisture retention, and patience. Rushing with high heat dries food out and creates uneven hot and cold spots. When in doubt, go lower and slower. Make sure leftovers reach an internal temperature of 165°F before serving.
Source: USDA Leftovers Safety | Last verified: March 26, 2026 | Our methodology