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