Prepare meatloaf mixture: In a large bowl, combine ground beef, eggs, breadcrumbs, Worcestershire sauce, ketchup, garlic powder, onion powder, oregano, salt, and pepper. Add sautéed vegetables and mix until combined.
Assemble meatloaf: Press half of the meatloaf mixture into the prepared loaf pan. Sprinkle with shredded provolone cheese, then top with remaining meat mixture. Press down firmly.
Bake meatloaf: Place meatloaf in the preheated oven and bake for 45-55 minutes, or until the internal temperature reaches 160°F (71°C).
Add cheese topping: Once meatloaf is fully cooked, remove from the oven and place slices of provolone cheese on top. Return to the oven and bake for 5-7 minutes until cheese is melted and bubbly.
Serve: Allow meatloaf to rest for 5-10 minutes before slicing. Garnish with fresh parsley if desired and serve hot. Enjoy with a side of mashed potatoes or a simple green salad.
