Preheat your oven to 375°F (190°C).

Heat the olive oil in a medium skillet over medium heat. Add the diced green bell pepper and onion, cooking for 5-6 minutes until softened and slightly golden. Remove from heat and let them cool for about 5 minutes.

In a large mixing bowl, combine the ground beef, breadcrumbs, egg, whole milk, Worcestershire sauce, garlic powder, salt, and black pepper. Mix gently with your hands until just combined—no dry breadcrumbs should be visible. Be careful not to overmix!

Press half of the meat mixture evenly into the bottom of a 9×5-inch loaf pan, creating a slight well in the center.

Layer 4 slices of provolone cheese over the meat, leaving a 1/2-inch border around the edges.

Spread the cooled pepper and onion mixture on top of the cheese.

Add the remaining meat mixture on top, pressing gently around the edges to seal in the filling.

Bake uncovered in the preheated oven for 45-50 minutes, or until the internal temperature reaches 160°F. The top should be nicely browned, and the edges should start to pull away from the pan.

In the last 5 minutes of baking, layer the remaining 4 provolone slices on top of the meatloaf and return to the oven until it’s melted and bubbly.

Allow the meatloaf to rest for 10 minutes before slicing. Use a sharp serrated knife and wipe between slices for clean cuts. If desired, garnish with fresh parsley.