Open-Face Cheeseburger Sub Recipe

Ingredients (16)

• 1 loaf ciabatta
• 3 medium cloves garlic, minced, crushed into a paste
• 1/4 cup extra-virgin olive oil
• 2 tablespoons unsalted butter
• 2 medium onions, halved, thinly sliced
• Kosher salt
• Pinch sugar
• 1 1/2 pounds ground beef (80/20 or 85/15)
• 3 tablespoons ketchup, plus more for serving
• 3 tablespoons Worcestershire sauce
• 2 tablespoons breadcrumbs
• 1/2 teaspoon freshly ground black pepper
• 1 egg
• 8 ounces sharp Cheddar, sliced or shredded
• Pickles, for serving
• Mustard, for serving