Old-Fashioned Grilled Cheese Burger
3 tablespoons EVOO, divided 1 small onion, very finely chopped 1 1/4 pounds ground beef 80/20 1 tablespoon Worcestershire sauce Salt and ground black pepper 8 slices sandwich bread or challah 3 to 4 tablespoons butter, softened 3 to 4 tablespoons mango chutney, optional 3 to 4 tablespoons Dijon mustard 8 slices cheddar cheese 8 slices lettuce 8 slices bacon, cooked until crisp (jalapeno style) 8 slices tomato Place a cast iron skillet over medium-high heat with 1 turn of the pan of EVOO, about 1 tablespoon. Add the onion to the pan and cook until tender, 4-5 minutes. Remove to a large mixing bowl and wipe the pan clean. When the onions have cooled slightly, place the pan back over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. To the mixing bowl with the onions, add the sirloin, Worcestershire, some salt and pepper and mix thoroughly to combine. Divide the meat into 4 portions and place between sep...