In a medium bowl, mix the olive oil, lemon juice, Worcestershire sauce, Dijon mustard, garlic, salt, black pepper, rosemary, and minced parsley. Whisk it well to combine thoroughly.
Add chicken to the bowl and toss to coat the chicken with the marinade thoroughly. Cover the bowl with plastic wrap and let the chicken marinate in the fridge for at least an hour or overnight.
Fire up the grill, drain the marinade and discard it, then place the chicken on the grill for 4-5 minutes per side or until the internal temperature reads 165℉ (74℃) on an instant-read thermometer. If using thicker breasts, cooking time will increase.
Optionally, cut the Romaine lettuce in half lengthwise and place it cut-side down on the grill for 1-2 minutes per side, flip, grill for another minute, and set aside. If you prefer not grilling your lettuce, simply cut it into bite-sized pieces and set it aside.
Transfer the grilled chicken to a cutting board, let it rest for 5-10 minutes, and slice it into small strips (about 3 inches). Set it aside while you prepare the remaining ingredients.
Mix the olive oil and garlic, then slice and brush the French bread with the olive oil and garlic mixture. Either toast it on the grill or in the oven. Or cut the slices into cubes, toast them, and use them like croutons.
Chop the Romaine lettuce into bite-sized pieces and place them on a serving platter, top with sliced chicken, and sprinkle with Parmesan cheese. Top your salad with a little of the dressing and serve the remaining dressing on the side for those who like drowning their salads.
Serve with the toasted French bread or croutons.