Preheat your oven to 350°F and position the oven rack in the center. Line a baking sheet with aluminum foil and coat it lightly with nonstick cooking spray.

Place the onion, carrot, celery, and garlic in a food processor fitted with a steel blade. Pulse until the vegetables are finely minced. Alternatively, these ingredients can be minced manually.

Heat olive oil in a medium skillet over medium heat. Add the minced vegetables and sauté, stirring often, for 5 to 7 minutes until softened, taking care not to brown them. Allow the mixture to cool slightly until warm.

In a large mixing bowl, whisk together the eggs, basil, Worcestershire sauce, salt, and pepper until combined.

Add the meatloaf mix, breadcrumbs, grated cheese, and cooled vegetable mixture to the bowl. Using clean hands, mix until the ingredients are evenly incorporated.

Shape the mixture into a loaf measuring approximately 9x5 inches directly on the prepared baking sheet. Spread the marinara sauce uniformly over the top, allowing it to cascade slightly over the edges.

Bake for 65 to 70 minutes, or until the internal temperature of the meatloaf reaches 160°F as measured by an instant-read thermometer. Let the meatloaf rest for 10 minutes after baking.

Carefully remove any rendered fat from the edges of the loaf, then transfer it to a cutting board or serving platter using a wide spatula. Slice into portions and serve with additional marinara sauce, if desired.