Cheeseburgers with Charred Green Chiles and Onions

Ingredients

• 6 onion rolls or sesame-seed hamburger buns
• ½ cup mayonnaise
• ½ cup prepared barbecue sauce
• 3 metal skewers
• 3 1/2-inch-thick onion slices
• 2 ¼ pounds freshly ground beef chuck
• 1 teaspoon salt
• + 4 more ingredients
• • Vegetable oil
  • 3 poblano chiles
  • 12 thin slices cheddar cheese
  • ½ teaspoon ground black pepper

Whisk mayonnaise and barbecue sauce in small bowl to blend. Cover and chill. Mix ground chuck with 1 teaspoon salt and 1/2 teaspoon pepper just to blend (do not overmix). Form mixture into six 1 1/2-inch-thick patties. Cover and let stand at room temperature 30 minutes. Prepare barbecue (medium-h...

View full recipe at Epicurious