Preheat your oven to 375°F (190°C) and grease your baking dish with olive oil.

In a large pot, bring salted water to a boil and cook the jumbo pasta shells until al dente, about 9-11 minutes.

Drain the shells and lay them on a clean towel to cool slightly.

In a mixing bowl, combine ricotta cheese, ¾ cup of shredded mozzarella, grated Parmesan, garlic powder, dried Italian herbs, and nutmeg if desired. Mix until well-blended.

Spread 1 cup of marinara sauce evenly across the bottom of the greased baking dish.

Stuff each pasta shell with the cheese mixture and place them seam-side up in the baking dish.

Pour the remaining marinara sauce over the filled shells and sprinkle the remaining shredded mozzarella on top.

Cover with aluminum foil and bake for 25 minutes, then uncover and bake for an additional 10 minutes until the cheese is golden and bubbly.

Let the dish cool for a few minutes before serving.