- 2 1/2 pounds ground sirloin
- About 1/3 cup Worcestershire sauce
- 4 to 6 cloves garlic, minced or grated
- 2 teaspoons chopped fresh oregano or 1 teaspoon dried oregano
- A handful chopped parsley
- Kosher salt and coarse black pepper
- Olive oil, to coat plus 2 tablespoons
- 2 onions, halved and thinly sliced
- 3 cubanelle peppers, halved, seeded and thinly sliced
- 1 fresh red or green chili pepper, seeded and thinly sliced or 1 teaspoon dried flakes
- 1 cup beef or veal stock
- 12 to 16 slices deli-cut provolone cheese
- 6 to 8 crusty rolls, lightly toasted
Combine beef, Worcestershire sauce, garlic, oregano, parsley, salt and pepper in a mixing bowl with your hands. Chill to combine flavors.
While meat chills, heat olive oil, 2 turns of the pan, over medium-high heat. Add onions, season with salt and pepper and let sweat 5 minutes. Add peppers and chili pepper, and cook 7-8 minutes more to soften. Keep onions and peppers moist and saucy with stock.
Bring meat to room temperature and form 6-8 patties that are thinner at the center than the edges for even cooking. Drizzle patties with olive oil to coat and cook over medium-high heat on a hot grill or griddle pan to desired doneness, about 8 minutes, turning once for pink center. Melt 2 slices of provolone over each patty in last minute of cooking time. Serve burgers on toasted crusty rolls and top with saucy peppers and onions.