Creating Three Cheese Manicotti is simple if you follow these clear steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Cook Manicotti Shells: Boil a large pot of salted water. Cook the manicotti shells for about 6-8 minutes, or until al dente. Drain and set aside to cool slightly.
3. Prepare Cheese Filling: In a medium bowl, combine ricotta cheese, shredded mozzarella, grated Parmesan, egg, basil, garlic powder, salt, black pepper, and Italian seasoning. Mix until well combined.
4. Fill Manicotti: Carefully stuff each manicotti shell with the cheese mixture using a spoon or a piping bag.
5. Prepare Baking Dish: Spread 1 cup of marinara sauce on the bottom of a 9×13 inch baking dish.
6. Arrange Manicotti: Place the filled manicotti shells in the baking dish over the sauce.
7. Top with Sauce: Pour the remaining marinara sauce over the shells, ensuring they are well-covered.
8. Add Cheese: Sprinkle extra mozzarella cheese on top, if using.
9. Cover with Foil: Cover the baking dish with aluminum foil to prevent over-browning.
10. Bake: Bake in the preheated oven for 30 minutes. Remove the foil and bake for an additional 15 minutes, until the cheese is bubbly and golden.
11. Cool: Allow the manicotti to cool for about 15 minutes before serving.

Following these steps will guide you in creating this incredible dish effortlessly.