01 -
Get your oven to 350°F (175°C) and let it heat up.
02 -
Take a big bowl and throw in the ground beef, breadcrumbs, egg, milk, onion, mushrooms, green pepper, Worcestershire sauce, garlic powder, and your seasonings. Blend it all together until it feels consistent.
03 -
Grab a loaf pan and push half the beef mix into it. Lay down slices of provolone, making sure to leave an edge. Add the rest of the beef mixture on top, sealing it shut around the edges.
04 -
Stir together ketchup, mustard, beef broth, and brown sugar in a small bowl. Pour it over the meatloaf, then bake for an hour. Once it’s out, leave it for 10 minutes before cutting.