Inside-Out Cheeseburgers with Made-From-Scratch Ketchup - Barbecuebible.com

Ingredients

• 1-1/2 pounds ground chuck
• 6 ounces smoked cheddar cheese, coarsely grated
• 2 scallions, trimmed and finely chopped
• Coarse salt (kosher or sea) and freshly ground black pepper
• Made-From-Scratch Ketchup ( see recipe )
• 4 hamburger buns, preferably brioche, or kaiser rolls
• 2 tablespoons butter, melted
• Lettuce leaves
• Tomato slices
• Pickle slices
• Paper-thin sweet onion slices (optional)