Place chicken breast halves between sheets of waxed paper; pound to 1/4-inch thickness. Sprinkle seasonings over chicken.
Heat a large nonstick skillet coated with cooking spray over medium heat. Add chicken; cook 4 to 5 minutes per side or until chicken is cooked through.
Spread mustard over chicken; top each breast half with a slice of ham and a slice of cheese. Cover skillet; reduce heat to low and cook 2 minutes or until cheese is melted.