Preheat oven to 350 degrees. In a large pot of boiling water, prepare manicotti according to the package directions. Drain and rinse in cool water.
In a medium bowl, stir together the ricotta, 1 cup of the mozzarella cheese, egg, Parmesan cheese, Italian seasonings, garlic powder, salt, and pepper. Place in a piping bag or a Ziploc bag with the corner cut off.
In a 9x13 baking dish, pour 1 cup of the marinara sauce on the bottom of the dish and spread in an even layer.
Take each manicotti shell and pipe about 2-3 tablespoons of the cheese mixture in each shell. This is easier if you pipe on one side and then the other side of the shell. Place in a single layer on the bottom of the baking dish.
Pour remaining marinara sauce on top and sprinkle with remaining 1 cup of mozzarella cheese.
Bake for 20-25 minutes or until cheese is melted and filling is warm.
Notes
FREEZER INSTRUCTIONS:
Prepare up to step 5. Wrap in plastic wrap and freeze up to three months. To eat, bake straight from frozen adding 10-15 minutes to the cook time or thaw in the fridge overnight and bake as directed.