Sprinkle chicken with salt and pepper. Place breadcrumbs on shallow plate. Beat egg white in a shallow bowl. Dip each chicken breast in egg white, letting excess drip off. Roll in crumbs, patting to coat well.
Combine spinach, egg yolk and nutmeg in small bowl. Heat oil in large skillet over medium-high heat. Add chicken breasts; cook 3 minutes per side or until golden brown. Reduce heat to low. Top each chicken breast with 1/4 of spinach mixture and 1 slice cheese. Cook, covered, 6 minutes or until chicken is no longer pink. Spoon pasta sauce over chicken.