Preheat the oven to 350°F. Spray a 9×13 inch baking pan with cooking spray and set aside.

Bring a large pot of water to a boil and cook shells until just al dente. Drain and rinse with cool water (Note: I always cook more shells than I think I’m going to need since a few inevitably break during the boiling process).

While the shells are boiling, brown ground turkey in a large saucepan. Drain fat and transfer ground turkey to a bowl. Add marinara sauce and mix well.

Stuff shells- first with half a spoonful (about half a tablespoon) of ricotta, then a spoonful (about a tablespoon) of meat sauce (as you can see, I wasn’t super exact about this part). Place shells in a prepared baking dish, with the opening up (Note: you should have some meat sauce leftover once all the shells are stuffed).

Sprinkle half of the mozzarella cheese on top of the shells, followed by the remaining meat sauce. Sprinkle the other half of the mozzarella on top of the sauce, then the parmesan cheese.

Bake for 20 minutes or until the sauce is hot and the cheese has melted.