This leftover turkey casserole has pasta and vegetables in a creamy sauce with a crispy cracker topping. Use your Thanksgiving leftovers to make it!
Leftover Turkey Casserole
I don’t like to let food go to waste, so I typically use Thanksgiving leftovers to make simple dinners for the week.
Making this easy turkey tetrazzini recipe is the perfect use for any leftover turkey in your fridge. It’s a fantastic comfort food, and much better than making endless sandwiches!
Slow Cooker Turkey Chili is another easy leftover turkey recipe. Just add everything at once and let your crockpot do the work. Or, make my Chicken Enchilada Casserole with turkey instead. It only has 5 ingredients and is ready in about 30 minutes.
Watch the video to see the process of making the casserole from start to finish! Look for it in the recipe card at the bottom of this post.
Ingredient Notes and Substitutions
- Turkey – Feel free to use cooked chicken instead! Cook up some chicken breasts or grab a rotisserie chicken from the store.
- Mushrooms – I like the extra savory flavor of baby Bella mushrooms (sometimes labeled as “cremini”), but regular white button mushrooms will work just fine.
- Frozen Peas – These add some color and another serving of vegetables, but you can certainly substitute another small frozen veggie (like carrots), or leave them out if you prefer.
- Shredded Cheese – Get a bolder flavor and a smoother sauce by shredding a fresh block of cheese. Pre-bagged shreds have an added preservative to prevent clumping that often gives the cheese a waxy texture.
- Butter Crackers – Ritz crackers are my favorite, but Panko breadcrumbs would make a great substitute for this leftover turkey recipe!
How to Make Easy Turkey Tetrazzini
This casserole recipe couldn’t be much simpler to make!
- Cook the spaghetti. Only cook the noodles to al dente. This means they should have a slight chewiness or “bite” to them.
- Chop the meat. While the spaghetti is cooking, you can chop up or shred your leftover turkey and set it aside to add to the sauce.
- Make the sauce. Start by sautéing the mushrooms in butter or oil. Then, you’ll add some flour to make a roux (a combination of fat and flour) to thicken the sauce.
PRO TIP: Whisk in the liquids SLOWLY to avoid clumps of flour.
- Combine sauce, turkey, and spaghetti in a casserole dish.
- Make the buttery cracker topping. Sprinkle it over the leftover turkey casserole and bake until bubbly and golden brown.
Because this meal is hearty and filling, it works as a complete meal all by itself.
Leftover Turkey Casserole FAQ
Can I make this casserole recipe ahead of time?
Sure! Just follow the recipe up until baking, but leave off the cracker topping. Wrap tightly with plastic wrap, and refrigerate overnight.
When you’re ready to bake, remove the plastic, add the topping, and bake as directed. You may need to add a few extra minutes since it’s going into the oven cold.
Would other cheeses taste good?
While I haven’t tried any others myself, I’m sure Pepper Jack or even mozzarella would taste great.
Can turkey tetrazzini be frozen?
Yes! Leftover turkey casserole freezes beautifully, so it is a great option for make-ahead meals!
Allow the dinner to cool completely in the dish, then cover tightly with plastic wrap and foil and freeze for up to 6 months.
When you’re ready to reheat it, first thaw in the refrigerator overnight. Then, bake until it’s bubbly and warmed through.
If you have a large enough sauté pan, you could double the recipe and split it between two baking dishes. Have one for dinner and freeze the other!
With love, from our simple kitchen to yours.
Other Easy Dinner Casseroles
Leftover Turkey Casserole + Video
- large pot for cooking spaghetti
- 1 pound spaghetti, cooked to al dente, drained, rinsed, and returned to the pot. See Notes
- 10 tablespoons unsalted butter, divided
- 1/2 cup diced onion
- 4 cloves garlic, minced
- 8 ounces baby bella mushrooms, sliced
- 1 teaspoon dried thyme
- 1 teaspoon kosher salt
- 1/2 teaspoon black pepper
- 1/2 cup all-purpose flour
- 2 1/2 cups chicken stock
- 2 1/2 cups whole milk, or 2% milk
- 8 ounces cream cheese, softened and cut into 8 pieces
- 16 ounces shredded cheddar cheese, divided
- 4 cups diced or shredded cooked turkey
- 1 1/2 cups frozen peas, unthawed
- 1 cup crushed butter crackers, such as Ritz
- 1/4 cup freshly grated parmesan cheese
- 3 tablespoons chopped flat leaf parsley, optional, for garnish
- Preheat the oven to 350°F. Grease a 9×13 inch baking dish with non-stick cooking spray or olive oil spray, and set dish aside.
- To a large sauté pan over medium-low heat, add 8 tablespoons of butter; allow it to melt.Add the onion and sauté, stirring occasionally, until onions are soft and translucent, about 5 minutes. Add the garlic and cook until fragrant, about 30 seconds.Add the mushrooms, thyme, salt, and pepper. Cook, stirring occasionally, until the mushrooms are softened, about 5 minutes.
- Add the flour to the pan and stir it in to coat the veggies. Cook for 2 minutes, stirring once or twice. Slowly and gradually, whisk in the stock, about 1/4 cup at a time, then add all of the milk. Stir to combine. Bring contents to a light boil over high heat, then immediately reduce heat to medium-low and simmer until thickened. Add the cream cheese and stir occasionally until melted. Add half of the cheddar cheese. Continue to cook, stirring occasionally until melted. Remove pan from the heat and stir in the cooked turkey and peas.
- Add sauce to the pot of cooked spaghetti and stir thoroughly to combine. Pour into the prepared baking dish, top with the remaining cheddar cheese, and set aside.
- Melt the remaining 2 tablespoons of butter in a medium-sized bowl in the microwave, or use a small pan on the stovetop. Add crushed crackers and shredded parmesan cheese to melted butter; stir to combine. Sprinkle cracker mixture evenly over top of casserole.
- Bake for 25-30 minutes, or until the top is golden brown. Garnish with chopped parsley if desired. Serve while warm.
- Pasta cooked to al dente means it should have a slight bite to it, but not undercooked or crunchy. (Pasta will finish cooking as the casserole bakes in the oven). After draining and rinsing spaghetti, return noodles to the cooking pot. Sauce will be combined with them later.
- May substitute spaghetti with any long thin pasta, such as spaghettini, angel hair, or fettuccine.
All nutritional information is based on third party calculations and is only an estimate. Each recipe’s nutritional value will vary depending on the ingredients used, measuring methods, and portion sizes.
Originally published September 2021.
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