Step 1

Get a pot of liberally salted water boiling (for the pasta).

Step 2

Preheat oven to 350°F.

Step 3

Melt the butter in a large saucepan/skillet over medium-high heat.

Step 4

Add the onion and celery and cook until soft and translucent, about 5 minutes.

Step 5

Add the mushrooms and cook until soft and starting to release their liquids.

Step 6

Add the sherry and cook for about 2 minutes.

Step 7

Add the pasta to the boiling water and cook until al dente, according to package directions.

Step 8

Sprinkle the flour on the mushroom mixture and stir. Cook for another 2 minutes.

Step 9

Stir in the chicken broth and milk. Stir until slightly thickened, about 4 minutes. Stir in the salt, pepper, and nutmeg. Stir in the cheddar cheese and ¼ cup of Parmesan cheese and continue mixing until melted and smooth.

Step 10

Stir in the turkey and peas. Stir to combine.

Step 11

Meanwhile, melt the remaining 2 tbsp butter and add with the breadcrumbs and remaining ¼ cup Parmesan in a small bowl.

Step 12

Spray your baking dish (or lasagna pan) with cooking spray. Transfer the turkey mixture into the pan and even out with the back of a large spoon. Sprinkle the breadcrumb mixture all over the top.

Step 13

Bake uncovered for 20 minutes, until bubbly. Place under the broiler for a minute or two if you want the bread crumbs more toasted (keep an eye on them, don't let them burn!). Serve at once.