Fruited Balsamic Chicken

I got this from my mother; this is from a yellowed, crumbling magazine insert, so who knows where it came from, or how old it is! (Could go back to the late 1960s.)

• Ready In: 45 mins
• Serves: 4

Ingredients

• 1⁄2 cup red onion, chopped
• 1 1⁄2 teaspoons  minced fresh thyme or 1⁄2 teaspoon dried thyme
• 1⁄2 teaspoon salt, divided
• 16  ounces boneless skinless chicken breasts
• 1⁄3 cup  raspberry preserves or 1⁄3 cup  apricot preserves or 1⁄3 cup  peach preserves or 1⁄3 cup  blackberry preserves
• 2  tablespoons  balsamic vinegar
• 1⁄4 teaspoon ground black pepper

Directions

1. Spray a nonstick skillet with cooking spray and heat over medium-high heat. Add onion and saute for 5 minutes. Sprinkle onion with thyme and 1/4 teaspoons salt.
2. Add chicken to pan; saute 6 minutes on each side, or until done. Remove chicken from pan and keep warm.
3. Reduce heat to medium. Add 1/4 teaspoons salt, preserves, vinegar, and pepper to pan, stirring constantly until preserves melt. Spoon sauce over chicken and serve immediately.