Make dinner spectacular with these spinach stuffed shells filled with three cheeses, frozen spinach, and marinara sauce. It's a five-star worthy dinner!
Bring salted water to a boil. Cook pasta shells 4 minutes short of package instructions.
In a large bowl, combine ricotta, parmesan cheese, one cup of mozzarella, Italian seasoning, egg, and squeezed spinach. Stir to combine together.
Spread half of the marinara sauce on the bottom of a baking dish (9X13 size). Fill each shell with the spinach ricotta mixture and place it in the baking dish.
Top the shells with remaining marinara sauce and mozzarella. Cover the dish with foil or a lid.
Bake at 375°F for 15 minutes. Remove the lid and bake for 10 more minutes or until cheese is a lightly golden color.