Preheat a smoker to 250°F. Set up a small foil pan or grill-safe skillet for the vegetables.

Heat the olive oil in a skillet over medium heat. Add the green pepper and onion, then cook for 5 to 7 minutes, stirring occasionally, until softened. Set aside to cool.

In a mixing bowl, combine the ground beef, egg, Parmesan, Worcestershire sauce, garlic powder, smoked paprika, salt, and black pepper. Mix gently just until combined.

Place the beef mixture on a sheet of parchment and shape it into a rectangle about ½ inch thick. Lay the provolone slices down the center, leaving a border around the edges. Spoon the cooled pepper and onion mixture over the cheese, then add the shredded provolone.

Use the parchment to help roll the beef around the filling. Pinch the seam and ends closed, then shape the loaf so the filling is fully enclosed. Place it seam-side down on a smoker-safe rack or tray.

Smoke the meatloaf until the center reaches 160°F on an instant-read thermometer, about 2 to 3 hours depending on the smoker and loaf shape. Let it rest for 10 minutes before slicing so the cheese settles inside.