Chicken Club Wraps

Name: Chicken Club Wraps
Ingredients: 1 pound boneless, skinless chicken breast, trimmed; ½ teaspoon freshly ground pepper, divided; 3 tablespoons nonfat plain Greek yogurt; 3 tablespoons cider vinegar; 3 tablespoons minced onion; 2 tablespoons extra-virgin olive oil; ⅛ teaspoon salt; 1 medium tomato, chopped; 1 avocado, chopped; 3 strips cooked bacon, crumbled; 8 large leaves red- or green-leaf lettuce; 4 10-inch flour tortillas, preferably whole-wheat