My simple Chicken Tetrazzini casserole is loaded with lean white meat, tender noodles, hearty mushrooms, and melty cheese in a creamy sauce—a family favorite in the making!
Bring a large pot of water to a boil over high heat. Season the water generously with salt, then add the pasta. Cook the pasta for 1 minute less than the package instructions, to al dente, then drain, rinse with cold water and set aside.
In a large pot or Dutch oven over medium-high heat, melt the butter. Add the mushrooms and cook, stirring occasionally, until they start to soften and turn golden.
Add the onion and cook for about 5 minutes, until softened, stirring occasionally.
Add the garlic and cook for 1 more minute. Once fragrant and softened, remove from the heat and transfer the mixture to a bowl.
For the Sauce:
Place the butter in the large pot and return it to medium heat. Once melted, whisk in the flour. Cook for 1 to 2 minutes while whisking to make a roux.
Whisk in the chicken stock until smooth. Then whisk in the milk, then heavy cream. Season with the salt and pepper. Cook for 8 to 12 minutes, whisking frequently, or until the mixture reaches a low boil and thickens.
Once thickened, add the cooked chicken, mushroom mixture, and parsley and stir to combine.
Stir in the pasta, 1½ cups of mozzarella (170g) and Parmesan cheese. Season with more salt and pepper to taste.
Transfer to 9x13-inch casserole dish, smooth out and top with the remaining ½ cup (55g) mozzarella cheese.
Bake for 30 to 35 minutes until the cheese on top is melted and the casserole is bubbling.
Video
Notes
For a gorgeously golden brown topping, place the casserole dish under the broiler for 2-3 minutes after baking.
If you’re using a rotisserie chicken, look for a large bird—about 3 pounds—to yield about 4 cups of cooked meat.
Salt your pasta water! You only get one chance to season your noodles, so don’t miss it.
Want to cut down on dirty dishes? Feel free to use an oven-safe pot like an enameled Dutch oven to boil the noodles and make the sauce, then toss everything together in the pot, sprinkle on the cheese, and bake directly without transferring to a casserole dish. The edges won’t get quite as crispy, and it’ll prevent the top from browning as well, but sometimes we all just need a little time-saver!