1. Prepare the Meatballs:

• In a large bowl, combine the ground beef, breadcrumbs, ¼ cup grated Parmesan cheese, beaten egg, minced garlic, finely chopped onion, fresh parsley, Italian seasoning, salt, and pepper.
• Use your hands to gently mix the ingredients until just combined. Be careful not to overmix, as this can make the meatballs tough. If the mixture feels overly dry, add 1-2 tablespoons of milk or water.
• Form the mixture into small meatballs, sized appropriately to fit comfortably inside a cooked jumbo shell. You should get approximately 20-24 meatballs, matching the number of shells you intend to stuff. Aim for meatballs about 1 to 1.5 inches in diameter.
• (Optional Browning Step): For extra flavour, you can lightly brown the meatballs. Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Add the meatballs in a single layer (work in batches if necessary) and brown them on all sides for about 4-5 minutes total. They don’t need to be cooked through at this stage, just browned. Transfer the browned meatballs to a plate lined with paper towels. Alternatively, you can skip browning and place the raw meatballs directly into the shells; they will cook through during baking.

2. Cook the Pasta Shells:

• Bring a large pot of generously salted water to a rolling boil.
• Add the jumbo pasta shells and cook according to the package directions, but aim for the lower end of the time range – cook them until they are al dente (tender but still firm to the bite). They will cook further in the oven, so slightly undercooking them prevents them from becoming mushy. Typically, this is about 8-10 minutes. Cook a few extra shells than you need, as some may tear or break during cooking or handling.
• Once cooked, carefully drain the shells using a colander. Immediately rinse them under cold running water to stop the cooking process and make them easier to handle. Gently separate any shells that are stuck together. Lay the cooked shells out on a baking sheet or clean surface in a single layer to prevent sticking while you prepare the rest of the dish.

3. Prepare the Baking Dish:

• Preheat your oven to 375°F (190°C).
• Spread about ½ to 1 cup of the marinara sauce evenly over the bottom of a 9×13 inch (or similar size) baking dish. This prevents the shells from sticking and adds a flavourful base.

4. Stuff the Shells:

• (Optional Ricotta Layer): If using, place a small spoonful (about ½ teaspoon) of ricotta cheese into the bottom of each cooked shell.
• Carefully take one cooked jumbo shell and gently place one meatball (raw or browned) inside it. The meatball should nestle snugly within the shell’s curve.
• Repeat this process with the remaining shells and meatballs.

5. Assemble the Dish:

• Arrange the stuffed shells in a single layer in the prepared baking dish, nestled closely together over the sauce base. Open side can be facing up or slightly tilted.
• Pour the remaining marinara sauce evenly over the top of the stuffed shells, ensuring they are well-coated. You want enough sauce to keep everything moist during baking, but not so much that it becomes soupy.
• Sprinkle the shredded mozzarella cheese evenly over the sauce-covered shells.
• Finally, sprinkle the remaining ¼ cup of grated Parmesan cheese over the mozzarella.

6. Bake the Stuffed Shells:

• Cover the baking dish loosely with aluminum foil. This helps trap steam and ensures the meatballs cook through and the shells stay moist.
• Place the dish in the preheated oven and bake for 30 minutes.
• After 30 minutes, carefully remove the aluminum foil.
• Continue baking, uncovered, for another 15-20 minutes, or until the sauce is bubbly, the cheese is melted and golden brown, and the meatballs are cooked through (internal temperature should reach 160°F or 71°C if checked with a meat thermometer).
• (Optional Broiling): If you prefer more browning on the cheese, you can switch the oven to the broil setting for the last 1-3 minutes. Watch very carefully during broiling to prevent burning.

7. Rest and Garnish:

• Once baked, carefully remove the dish from the oven. Let it rest for 5-10 minutes before serving. This allows the cheese and sauce to set slightly, making it easier to serve without falling apart.
• Garnish generously with chopped fresh basil or parsley, if desired, just before serving.