These beef patties are infused with intense seasoning and topped with layers of condiments. You'll find pre-made guacamole in delis, and it is sold in tubs in the refrigerated section of most supermarkets.

16 ounces ground beef chuck (80% lean)
½ cup finely chopped onion
2 chipotle chilies in adobo sauce (seeds removed), finely chopped, with 1 tablespoon sauce (see Tip)
½ teaspoon salt
4 hamburger buns, halved horizontally
½ cup guacamole
2 cups finely shredded romaine lettuce
4 (3/8-inch-thick) tomato slices
½ cup bottled tomato salsa plus extra for accompaniment

Prepare the outdoor grill for cooking over medium-hot charcoal or moderate heat for gas (if using).

Mix together the beef, onion, chilies with sauce, and salt in a medium bowl. Form into four (4 ½-inch) patties (¾-inch-thick) with your hands.

Grill the burgers on a lightly oiled grill rack, for 4 minutes, turning once, for medium-rare. Or cook for longer, if desired.

Meanwhile, toast the buns. To assemble each burger, spread 2 tablespoons salsa on the cut side of the bun bottom. Top with a cooked patty, tomato slice, and ½ cup lettuce. Spread the cut side of the bun top with 2 tablespoons guacamole. Add to the burgers, spread-side down.