1In small bowl, mix all dressing ingredients until blended; set aside.
2Spray 10-inch skillet with cooking spray; heat over medium-high heat. Cook chicken in skillet 15 to 20 minutes, turning once, until juice of chicken is clear when center of thickest part is cut (170°F). Remove chicken to cutting board.
3Add dressing to skillet; stir to loosen any pan drippings.
4Cut chicken into slices. Among 4 plates, divide spinach. Top with chicken, strawberries and cheese. Drizzle with dressing. Sprinkle with walnuts.