Created by ellie on July 3, 2017
Step 1: Build a medium-heat fire in a charcoal grill or heat a gas grill to medium.
Step 2: Form meat into 6 patties; season with salt and pepper.
Step 3: Heat a cast-iron skillet on grill; place patties in skillet and top with onion slices. Cover with grill lid and cook 3-5 minutes; flip burgers, resting them on top of the onion slices and cook 2 minutes more. Top with cheese slices and cook until cheese melts (a minute or two); keep warm.
Step 4: Working in batches, grill buns, lettuce, pickles and tomatoes, turning once until charred (2 minutes for buns, 3-4 for romaine, and 5-7 minutes for pickles and tomatoes), turning once until charred.
Step 5: Divide patties, vegetables and condiments between buns (or simply serve all separately and let people fix their own burgers)