Heat a large skillet to medium high heat and add ground beef in one whole piece. Brown the ground beef whole on both sides until golden, about 2-3 minutes per side.

Once browned, crumble into small pieces and continue to cook until the meat is no longer pink, about 5 minutes. Transfer cooked meat to a plate and set aside.

To the same skillet, melt butter, then add onion, green pepper, and mushrooms. Sauté until mushrooms are golden brown, about 6-7 minutes.

Add ground beef back to the skillet with the veggies along with Worcestershire sauce, onion soup mix, garlic powder, kosher salt, and black pepper. Stir to combine and cook another 2-3 minutes. Remove from the heat.

Turn the broiler to high and place the top rack a few inches from the heat source.

Divide the meat mixture between the hoagie rolls and top each roll with a slice of provolone cheese.

Place the rolls on a broiler safe pan and broil for 30-seconds to 1-minute, or until the cheese is melted and bubbly. Enjoy right away!