Preheat oven to 375°F.
Cook the pasta to al dente according to the package directions.
3 cups dry rotini
Heat 2 tablespoons of butter in a large skillet over medium heat.
4 tablespoons unsalted butter
Once heated, add in the onion, carrots, and salt. Sauté until softened.
½ onion, 2 carrots, ½ teaspoon kosher salt
Stir in the garlic, thyme, and rosemary, and cook for a minute.
2 cloves garlic, 1 teaspoon chopped fresh thyme, 1 teaspoon chopped fresh rosemary
Stir in the flour. Then, slowly pour in the chicken broth while whisking.
2 tablespoons all-purpose flour, 14.5 ounces low-sodium chicken broth
Bring the mixture to a boil, and reduce to a simmer. Continue whisking until the mixture is creamy and smooth.
Pour in the heavy cream and turkey gravy and whisk to combine.
¾ cup heavy cream, ½ cup turkey gravy
Add in the turkey, peas, and pasta, and stir to combine. Season with salt to taste.
3 cups chopped cooked turkey, 1 cup peas
Transfer the mixture to a casserole dish.
Melt the remaining 2 tablespoons of butter and combine it with the breadcrumbs in a small dish.
1 cup breadcrumbs
Sprinkle the breadcrumbs over the casserole.
Bake for about 20-25 minutes until the breadcrumbs are golden brown and the casserole is bubbling.