Gather the ingredients and preheat oven to 350 F.
![Turkey, Ham, and Swiss Casserole]()
Grease a 2-quart baking dish.
![Turkey, Ham, and Swiss Casserole]()
Cook pasta (you can use mini fusilli or farfalle, macaroni, or other shapes) in boiling salted water following package directions. Drain, rinse and set aside.
![Turkey, Ham, and Swiss Casserole]()
Heat butter in a large skillet and saute the onion and celery over medium-low heat until softened.
![Turkey, Ham, and Swiss Casserole]()
Add ham and stir in flour until well combined.
![Turkey, Ham, and Swiss Casserole]()
Gradually stir in the milk until thickened. Add marjoram, salt, and pepper. Stir in the cheese, turkey, and peas and carrots, if using.
![Turkey, Ham, and Swiss Casserole]()
Add the cooked pasta and blend thoroughly. Spoon the pasta mixture into the prepared baking dish.
![Turkey, Ham, and Swiss Casserole]()
Combine breadcrumbs with 1 tablespoon melted butter; sprinkle over the top of the casserole.
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Bake for 25 to 30 minutes, until bubbly and the topping is browned.
![Turkey, Ham, and Swiss Casserole]()
Serve and enjoy!
![Turkey, Ham, and Swiss Casserole]()