1 lb lean ground beef
1/2 teaspoon garlic powder
2 tablespoons butter
1 small yellow onion, diced
1 green bell pepper, seeded and diced
2 tablespoons ketchup
1 tablespoon Worcestershire sauce
1 tablespoon cornstarch
1 cup beef broth
8 oz provolone cheese slices
6 hamburger buns
Kosher salt and freshly ground black pepper, to taste
Add ground beef, garlic powder, salt, and pepper, to a large skillet and cook until browned. Remove beef to a plate and set aside.
Add butter, onions, and peppers to the skillet and brown until softened, 4-5 minutes.
Return beef to skillet and stir in ketchup and Worcestershire sauce. Mix cornstarch into a 2 tablespoons of the beef broth and add to pan. Stir in rest of beef broth.
Let simmer until most liquid has absorbed and adjust seasoning as needed.
Remove from heat, add provolone cheese and serve on toasted hamburger buns.