Preheat oven to 350 degrees. Spray a 13” x 9” baking dish with olive oil. Cook pasta according to package directions. When pasta is cooked, drain well and pour it into a prepared baking dish. Add both marinara jars, the ricotta and spinach and stir until the sauce is evenly distributed. Cover with foil and bake for 25 minutes. Remove the dish from the oven, take off the foil and sprinkle on the shredded cheese. Place under the broiler for about 5 minutes or until cheese is melted and golden.