Filling:

• 1 tablespoon olive oil
• 1 pound lean ground beef
• 1 small onion, finely diced
• 1 green pepper, diced
• 4 cloves garlic, minced
• 1 cup reduced sodium beef broth
• 1 tablespoon cornstarch
• 1 ½ teaspoons beef bouillon
• 2 tablespoons ketchup
• 2 tablespoons Worcestershire sauce
• 1 teaspoon Dijon mustard
• 1 tsp dried oregano
• 1 tsp dried parsley
• 1/2 tsp salt
• 1/2 tsp pepper
• 1/2 tsp dried basil
• 1/2 tsp paprika
• 1/4 tsp red pepper flakes
• 3/4 cup sharp cheddar cheese, freshly grated

Buns:

• 6 brioche hamburger buns
• Softened butter or mayo for brushing (optional)
• 6 slices provolone cheese