12 oz lean ground chuck 2 oz Gorgonzola cheese or other blue cheese Vegetable oil 4-1/2-inch-thick slices country-style white bread 2 large tomato slices 4 thin slices red onion 1/2 bunch arugula
Form beef into four 3-inch-diameter patties. Form cheese into two 1-1/2-inch rounds; place cheese atop two beef patties. Top each with another beef patty, sealing at edges. Season with pepper. Prepare barbecue (medium-high heat) or preheat broiler. Brush barbecue rack with vegetable oil. Grill burgers until charred outside but still juicy, about 3 minutes per side. Grill bread slices until lightly toasted, about 1 minute per side. Place each burger on 1 bread slice. Top with tomato, onion, arugula and another bread slice and serve. Two servings; can be doubled.