1. Cover the steak with a piece of non-stick baking paper. Flatten with a meat mallet or rolling pin until 1cm thick. Repeat with remaining steaks then brush with olive oil.
2. Spray a cast iron grill or barbecue hot plate with non-stick cooking spray. Heat to medium-high, then cook the bacon (three minutes each side) and steaks (one minute each side, or to your liking).
3. Meanwhile, lightly toast the bread, spread with butter and place two slices on each plate. Top with lettuce, tomato, bacon, steak and a dollop of relish. Top with remaining toasted bread, then slice in half and serve.