1. Heat oil in a nonstick skillet over medium-high heat.
2. Sauté onions 3-5 minutes.
3. Season chicken with thyme, salt and pepper.
4. Add chicken to skillet and cook 6-8 minutes on each side or until cooked through.
5. Remove chicken from skillet, keep warm.
6. Reduce heat and stir in preserves and vinegar, stirring until preserves melt.
7. Serve raspberry sauce over chicken.