The Grandaddy of All Hamburgers Recipe - Barbecuebible.com

Ingredients

• 1-1/4 pounds ground chuck
• 1-1/4 pounds ground sirloin
• Coarse salt (kosher or sea) and freshly ground black pepper
• 1/2 medium-size onion, cut into 8 thin wedges
• 16 slices sandwich bread
• 3 tablespoons butter, melted (optional)
• 1 large or 2 medium-size gorgeous, luscious, ripe red tomatoes, thinly sliced
• 8 Boston lettuce leaves or iceberg lettuce slices
• Cheese Sauce (optional; recipe follows)