This burger blend of hot Italian sausage and ground beef is topped with charred peppers and onions, provolone cheese and warm marinara sauce, hitting those classic notes of sausage and peppers in a new and unique way.
Combine the ground beef, sausage, garlic, oregano, 1/4 teaspoon salt and a few grinds of pepper in a medium bowl; mix with your hands until just combined. Form into four 3/4-inch-thick patties; set aside.
Preheat a grill pan or grill over medium heat. Toss the onion and bell peppers with the olive oil, 1/4 teaspoon salt and a few grinds of pepper in a bowl. Grill the vegetables, turning occasionally, until lightly browned and tender, about 7 minutes. Transfer to a plate and set aside.
Brush the grill pan with olive oil. Add the burgers and cook until browned and cooked through, about 4 minutes per side, topping with the cheese and covering during the last 2 minutes.
Serve the burgers on the buns and top with the onion-pepper mixture, basil and marinara sauce. Serve with chips.