1. 1. Begin by bringing a large pot of salted water to a boil. Gently add the jumbo pasta shells and cook them until they’re just tender, about 8-10 minutes. Drain the shells and rinse them briefly under cold water to stop the cooking process and prevent them from sticking together.

2. 2. In a skillet over medium-high heat, brown the ground beef, breaking it up into small crumbles as it cooks. Season the beef with the Italian seasoning, salt, and pepper, ensuring it’s well-seasoned and full of flavor.

3. 3. In a large bowl, combine the ricotta cheese, egg, 1 cup of mozzarella, and 1/2 cup of Parmesan. Stir in the cooked ground beef until the mixture is thoroughly combined and creamy.

4. 4. Preheat your oven to 375°F. Carefully spoon the beef and ricotta mixture into each of the cooked pasta shells, filling them to the brim. Arrange the stuffed shells in a baking dish, making sure they’re snug but not overcrowded.

5. 5. Pour the marinara sauce over the top of the stuffed shells, making sure to cover them evenly. Sprinkle the remaining 1/2 cup of mozzarella cheese over the top. Bake the Beef-Stuffed Shells for 25 minutes, or until the cheese is melted and bubbly.

6. 6. Garnish with freshly chopped basil before serving.