Remove the outer leaves from the iceberg lettuce and discard. Wash the remaining lettuce head and pat it dry. Place it onto a large cutting board. Cut the lettuce head in half, and then cut each half again. Cut the core off from the wedges.
Heat a large frying pan over medium-high heat until hot, add bacon slices, and cook on both sides until the bacon is brown and crispy. Remove from the skillet and place them onto a paper towel. Once cooled down, cut into pieces.
Place the iceberg wedges onto the serving plates and drizzle generously with the blue cheese dressing.
Top the wedges with diced tomatoes, blue cheese crumbles, bacon, and scallions. Serve immediately.