Ingredients

1 pound spaghetti (cooked to al dente, drained, rinsed, and returned to the pot)

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)

Instructions

Step 1: Preheat the oven to 350°F. Grease a 9×13 inch baking dish with non-stick cooking spray or olive oil spray, and set aside.

Step 2: In a large sauté pan over medium-low heat, melt 8 tablespoons of butter. Add the diced onion and sauté, stirring occasionally, until soft and translucent, about 5 minutes. Add minced garlic and cook until fragrant, about 30 seconds.

Step 3: Add sliced mushrooms, thyme, salt, and pepper to the pan. Cook, stirring occasionally, until mushrooms are softened, about 5 minutes.

Step 4: Sprinkle the flour over the vegetables and stir to coat. Cook for 2 minutes, stirring occasionally. Gradually whisk in the chicken stock, about 1/4 cup at a time, then add all the milk. Stir to combine and bring to a light boil over high heat. Reduce heat to medium-low and simmer until thickened.

Step 5: Add cream cheese pieces to the pan and stir occasionally until melted. Stir in half of the shredded cheddar cheese until melted. Remove from heat, then stir in the cooked turkey and unthawed peas.

Step 6: Pour the sauce over the cooked spaghetti in the pot and stir thoroughly to combine. Transfer the mixture to the prepared baking dish. Sprinkle the remaining cheddar cheese evenly over the top.

Step 7: Melt the remaining 2 tablespoons of butter in a microwave-safe bowl or small pan. Add crushed crackers and grated parmesan cheese to the melted butter, stirring to combine. Sprinkle this mixture evenly over the casserole.

Step 8: Bake for 25-30 minutes, or until the top is golden brown. Garnish with chopped parsley if desired. Serve warm.

Tips & Variations

For a lighter version, substitute half the butter with olive oil and use low-fat milk.

Swap out chicken stock for turkey stock or vegetable broth for a different depth of flavor.

Add a pinch of red pepper flakes for a subtle spicy kick.

Use gluten-free flour and pasta to make this casserole gluten-free.

FAQs

Can I use other types of pasta for this casserole?

Yes, while spaghetti works well, you can substitute with other pasta shapes like penne, rotini, or fettuccine. Just adjust cooking times so the pasta is al dente before mixing with the sauce.

Is it necessary to rinse the cooked spaghetti?

Rinsing the spaghetti after cooking helps to stop the cooking process and prevents the noodles from sticking together, which is helpful for mixing with the sauce later. However, if you prefer, you can skip rinsing and toss the pasta immediately with a little oil to keep it separate.