Preheat the oven to 325 degrees F. Place garlic and 2 Tbsp. olive oil in a small baking dish, cover and roast 20 minutes, or until the garlic is tender. Transfer garlic and oil to a bowl. With the back of a small spoon, mash garlic into small pieces, and then cool to room temperature. Now mix in the mayonnaise, cheese, lemon juice, water, Worcestershire, salt and pepper. Cover and refrigerate dressing until needed.
Preheat indoor grill or barbecue to medium-high. Brush the steaks with the 1 Tbsp. olive oil; season with salt and pepper. Grill steaks to desired doneness, allowing 2–3 minutes per side for rare, and 3–4 minutes for medium-rare to medium. Transfer steaks to a cutting board, let rest
5 minutes, and then cut into thin slices.
Divide and arrange lettuce on 4 dinner plates. Arrange the slices of steak, tomatoes and celery on top of the lettuce. Spoon some of the roasted garlic Parmesan dressing on each salad and serve.