Pre-heat a nonstick griddle or skillet to medium. Grill each side of the chicken breast for 5-7 minutes. Spread one side of the Sandwich Thins® roll with reduced-fat mayonnaise. Assemble the sandwich by layering a slice of cheese, apples, chicken, baby spinach and the remaining slice of cheese.
Grill the sandwich about 90 seconds on each side, weighing the sandwich down with a small skillet as it cooks.