Preheat your oven to 375°F (190°C) and lightly grease a 9x13” baking dish with nonstick spray.

In a large skillet, melt 4 tablespoons of unsalted butter over medium heat. Add the diced yellow onion and a sprinkle of kosher salt, sautéing for about 4-5 minutes until the onion turns translucent.

Mix in minced garlic, dried thyme, and freshly ground black pepper, cooking until fragrant, about 1 minute.

Sprinkle 1/4 cup of all-purpose flour into the skillet, stirring for about 1 minute. Gradually pour in 1/2 cup of white wine while continuously stirring to avoid lumps.

Add 2 cups of chicken stock, bring to a gentle boil before stirring in 8 ounces of cream cheese. Cook until melted and smooth.

Incorporate 8 ounces of sliced cremini mushrooms and 1 cup of frozen peas into the sauce, then pour in 1 cup of half and half. Sprinkle with remaining kosher salt.

Let the mixture simmer for about 5 minutes until mushrooms soften and sauce thickens.

Remove from heat and gently fold in 3 cups of cooked turkey, 1 1/4 cups of Italian blend cheese, 1/4 cup of chopped parsley, and the juice of 1 lemon.

Carefully add in the cooked spaghetti, ensuring every strand is coated in the creamy sauce.

Transfer the mixture to the greased baking dish. Sprinkle remaining cheese on top.

In a small bowl, combine 1 cup of panko breadcrumbs, 1/4 cup of grated Parmesan cheese, and a bit of parsley before sprinkling over the casserole.

Bake for 18-20 minutes until cheese is bubbly and golden. Increase time by an additional 3-5 minutes to toast the topping.

Once baked, let the casserole rest for about 5 minutes before serving.