1Heat oven to 375°F. Spray square pan, 9x9x2 inches, with cooking spray. Flatten each chicken breast half to 1/4-inch thickness between sheets of plastic wrap or waxed paper. Sprinkle with salt and pepper.
2Cut cheese into 4 slices, about 3x1x1/4 inches. Place 1 slice cheese on center of each chicken breast half. Roll chicken around cheese, folding in sides. Brush butter over chicken rolls. Place chicken, seam sides down, in pan.
3Bake uncovered about 30 minutes or until chicken is no longer pink in center. Serve with salsa. Sprinkle with cilantro.