1-Preheat the oven: Preheat the oven to 350 degrees F and lightly coat a 9×13-inch baking dish with cooking spray.

2-Cook the pasta shells: Cook the 20 jumbo pasta shells in salted water, boiling them for 1-2 minutes less than the package instructions to make stuffing easier; drain and set aside.

3-Prepare the meat sauce: In a skillet over medium heat, heat 2 tablespoons olive oil and sauté the 1 small chopped onion and 3 cloves minced garlic for about 3 minutes until fragrant, then add ½ pound ground beef and cook until browned. Stir in 24 ounces pasta sauce and simmer on low heat.

4-Make the cheese mixture: In a separate large bowl, beat 1 egg, then mix in 15 ounces ricotta cheese, 1 cup of the shredded mozzarella cheese, ½ cup grated Parmesan cheese, and 2 tablespoons dried parsley until well combined.

5-Spread sauce and stuff shells: Spread one-third of the meat sauce evenly in the bottom of the prepared baking dish. Stuff each of the 20 cooked pasta shells with the cheese mixture and arrange them in the dish. Pour the remaining sauce over the shells.

6-Bake and finish: Cover the dish with aluminum foil and bake for 30 minutes. Remove the foil, sprinkle the remaining 1 cup shredded mozzarella cheese over the shells, and bake uncovered for an additional 5 to 10 minutes, or until the cheese is melted. Let the dish rest for a few minutes before serving to allow flavors to settle. This method keeps the shells tender and the filling gooey, perfect for any occasion.