These stuffed manicotti are cheesy, rich and delicious. Use a package of thawed frozen spinach for the cheese filling and your favorite jarred marinara or homemade (even better). Makes a great vegetarian meal that the whole family will enjoy!
Cook the manicotti noodles to 2 minutes before "al dente" according to the manufacturers instructions. Drain the noodles and transfer to a rimmed sheet pan. Drizzle with a teaspoon of olive oil to coat and set aside to cool.
Squeeze all of the liquid out of the spinach until it's mostly dry. (You can do this with your clean hands, or my preferred method is to wrap it in a clean dish towel, secure the ends and twist and squeeze with a lot of pressure, so the excess liquid leaks out.) Set aside.
In a large skillet, heat the remaining olive oil over medium heat. Add the minced garlic and cook for 1-2 minutes until the garlic softens and is fragrant.
Stir in the basil, oregano, crushed red pepper, salt and black pepper and cook for one minute until fragrant. Add the spinach and cook, stirring regularly for about 1-2 minutes or until well mixed. Remove from the heat and set aside.
Add the chopped bell pepper to the spinach mixture and stir well to combine.
Add the ricotta, 1 cup of grated mozzarella and the grana adana cheeses to the spinach mixture. Make a well in the center of the cheese and add the egg. Whisk the egg and gradually incorporate the cheeses and spinach mixture until everything is well blended.
Transfer the spinach mixture to a large disposable piping bag (or use a quart sized zip top storage bag and seal it.) Snip the end off the bag to allow for a 1/2" opening.
Spread 1 to 1½ cups of marinara sauce in the bottom of the baking dish. Set aside.
Insert the end of the bag into a cooked manicotti noodle and squeeze the filling into the pasta. Transfer the pasta to the baking dish. Continue stuffing the manicotti with the ricotta and spinach mixture, until all the noodles are filled and the casserole is full.
Spoon the remaining marinara over the pasta and top with the remaining mozzarella cheese. Cover with foil and bake for 25-30 minutes or until the cheese is melted and the sauce is bubbling. Serve.