Ingredients
- 1 pound lean ground beef
- 2 tablespoons butter
- 1 small yellow onion diced
- 1 small green bell pepper diced
- 8 ounces brown mushrooms minced
- 2 tablespoons ketchup
- 1 tablespoon Worcestershire sauce
- 1/2 teaspoon Kosher salt
- 1/2 teaspoon fresh ground black pepper
- 1 tablespoon cornstarch
- 1 cup beef broth
- 8 ounces Provolone
- Slices chopped (use 6oz if you don’t want it very cheesy)
- 6 brioche hamburger buns
