Turn your surplus Thanksgiving Turkey into a comforting Leftover Turkey Casserole with creamy cheese sauce, pasta, and a crunchy breadcrumb topping.
Leftover turkey casserole is the ultimate way to enjoy your holiday leftovers in a brand-new way. I remember the first time I made this dish—it was the day after Thanksgiving, and I had a fridge full of turkey and a craving for something hearty. I wanted a dish that was warm, creamy, and had just the right balance of textures. After a little experimenting, this casserole came together. The creamy cheese sauce, tender turkey, and crunchy breadcrumb topping instantly became a family favorite. It’s been a go-to ever since!
Why This Recipe Works
- Easy to Make: This casserole is a simple, one-pan meal that uses up your leftover turkey in the most delicious way.
- Flavor-packed: The combination of creamy cheese sauce, savory turkey, and sautéed mushrooms makes every bite comforting and full of flavor.
- Versatile: You can easily adjust the ingredients to suit your tastes or what you have on hand, making it a great option for customizing.
Ingredient Notes
- Rotini Pasta: 1 pound of dry rotini for a hearty base.
- Mushrooms: 12 ounces, sliced, for an earthy flavor
- .Onion & Garlic: Adds a savory and aromatic foundation.
- Frozen Peas: 1 cup, for pops of sweetness and color.
- Milk: 2½ cups whole milk for a rich, creamy sauce.
- Cheddar & Parmesan Cheese: These cheeses add gooeyness and sharp flavor—2 cups cheddar and 1¾ cups parmesan.
- Butter & Olive Oil: To sauté the aromatics and mushrooms.
- Breadcrumbs & Parsley: Panko breadcrumbs for crunch and parsley for freshness.
- Mustard: A tablespoon for depth of flavor.
- Kosher Salt: Enhances all the other ingredients.
Step By Step Instructions
You can find the full, printable recipe at the bottom of this post (click the button above), but you can read a summary with step-by-step instructions and photos for each step below.
Cook the Noodles:
Cook 8 ounces (225 g) of rotini pasta in salted water until very al dente (slightly undercooked). Drain the pasta well and transfer it to a casserole dish. Set it aside.
Prepare the Mushrooms:
In a microwave-safe bowl, place 1 cup (100 g) of sliced mushrooms and microwave them on high for 4 minutes. After microwaving, drain any excess water.
Make the Creamy Sauce:
Heat 2 tablespoons (30 mL) of olive oil over medium heat in a medium saucepan. Add the chopped onion and sauté for 3-4 minutes until translucent.
Add the minced garlic and the microwaved mushrooms to the onions, cooking for another 1-2 minutes.
Stir in 6 tablespoons (45 g) of all-purpose flour, cooking for about 1 minute to remove any uncooked flour taste.
Gradually whisk in 3 cups (720 mL) of whole milk, stirring constantly to avoid lumps. Add 2 teaspoons (10 mL) of Dijon mustard and 1 teaspoon (1 g) of chopped fresh parsley.
Bring to a simmer, and cook until thickened and bubbling.
Stir in 1 ¼ cups (150 g) of shredded cheddar cheese until melted and smooth. Season with ¾ teaspoon (4 g) salt and ½ teaspoon (2 g) black pepper.
Pour the sauce over the pasta in the casserole dish. Stir in 1 ½ to 2 cups (225-300 g) of cooked leftover turkey and ¾ cup (100 g) of frozen green peas. Mix everything until well combined, then spread evenly in the dish. Preheat your oven to 350°F (175°C) and bake for 15 minutes.
In a small bowl, mix 2 tablespoons (30 mL) of olive oil, 2 tablespoons (15 g) of breadcrumbs, 1 tablespoon (5 g) of grated Parmesan cheese, and a pinch of salt. Stir until the breadcrumbs are coated.
After 15 minutes of baking, remove the casserole from the oven. Sprinkle ¾ cup (85 g) of shredded cheddar cheese on top, then add the breadcrumb mixture. Return the casserole to the oven for an additional 5 minutes or until the cheese is melted and bubbly. Let it rest for 3 to 5 minutes, garnish with fresh parsley, and serve warm.
Erren’s Top Tips
- Use less sauce on your Leftover Turkey Casserole if you prefer a drier casserole. The extra sauce option makes for a creamy dish, but reducing it will give you a firmer texture.
- If you don’t have leftovers, use rotisserie chicken as a substitute for turkey.
- For a healthier version, you can substitute low-fat milk and reduced-fat cheese without losing too much flavor.
Storage & Freezing Instructions ❄
Storage: This casserole will be kept in the fridge for up to 3 days in an airtight container. To reheat, microwave or warm it in the oven until heated.
Freezing: Let the casserole cool completely if you want to freeze it. Wrap it tightly in plastic wrap and aluminum foil, and store it in the freezer for up to 2 months. To reheat, thaw it in the fridge overnight and bake at 350°F (175°C) for 20-25 minutes.
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Let’s Make Leftover Turkey Casserole
Ingredients
- 1 lb dry rotini
- 12 oz mushrooms sliced
- 2 tablespoons unsalted butter
- 2 tablespoons olive oil
- 1 onion chopped
- ½ teaspoon kosher salt
- 3 cloves garlic minced
- 2 tablespoons chopped fresh parsley
- 2½ cups milk
- 2 cups grated cheddar cheese divided
- 1¾ cups parmesan cheese grated
- 1 tablespoon mustard
- 2 cups leftover turkey shredded or chopped
- 1 cup frozen peas
For the Topping
- ½ cup panko breadcrumbs
- 2 tablespoons parmesan cheese grated
- 2 tablespoons olive oil
- 2 cloves garlic minced
- Flat-leaf parsley chopped
Instructions
- Bring a large pot of salted water to a boil. Add the dry rotini and cook until just under al dente (about 1-2 minutes less than the package instructions). Drain and set aside.
- Place the sliced mushrooms in a microwave-safe bowl and microwave on high for 4 minutes. Drain any excess liquid and set aside.
- In a large skillet, heat the butter and olive oil over medium heat. Add the chopped onion and kosher salt, sautéing for 3-4 minutes until softened. Stir in the garlic and cook for 30 seconds until fragrant. Add the mushrooms and parsley, cooking for 2 minutes.
- Reduce the heat to low and pour in the milk, stirring constantly. Gradually add 1½ cups of the cheddar cheese and parmesan cheese, stirring until melted and smooth. Stir in the mustard and remove from heat.
- In a large mixing bowl, combine the cooked pasta, cheese sauce, turkey, and frozen peas, mixing until evenly coated.
- Preheat the oven to 350°F (175°C). Spread the pasta mixture into a greased 9×13-inch baking dish. Sprinkle the remaining ½ cup of cheddar cheese evenly over the pasta.
- In a small bowl, mix the panko breadcrumbs, parmesan cheese, olive oil, garlic, and parsley. Sprinkle this breadcrumb mixture evenly over the cheddar cheese layer.
- Bake for 25-30 minutes, or until the casserole is bubbling around the edges and the topping is golden brown. If the topping browns too quickly, cover loosely with foil.
- Let the casserole rest for 5-10 minutes before serving. Garnish with extra parsley if desired. Enjoy!
Tips + Notes
- Use less sauce if you prefer a drier casserole. The extra sauce option makes for a creamy dish, but reducing it will give you a firmer texture.
- If you don’t have leftovers, use rotisserie chicken as a substitute for turkey.
- For a healthier version, you can substitute low-fat milk and reduced-fat cheese without losing too much flavor.
Linda Y says
The step by step does not match the printed recipe. For instance, the printed recipe has no turkey
Erren Hart says
It’s too cups of leftover turkey that’s chopped or shredded. I don’t know how that was missed, but I’m grateful you caught it so quickly! Thank you, Linda!