Delicious Raspberry Chicken

4 boneless skinless chicken breast halves (6 ounces each)
2-1/4 cups fresh raspberries
4 teaspoons sugar
1/4 cup apple juice
2 tablespoons red wine vinegar
1 tablespoon soy sauce
1/2 teaspoon minced garlic
1/8 teaspoon dried thyme
1 tablespoon cornstarch
1 tablespoon cold water
1 tablespoon vegetable oil

1 tablespoon butter
Additional fresh raspberries, optional

Flatten chicken to 1/4-in. thickness; set aside. In a small bowl, mash together raspberries and sugar; mash again after 15 minutes. Strain raspberries, reserving juice; discard pulp and seeds. In a small saucepan combine and bring to a boil, raspberry juice, apple juice, vinegar, soy sauce, garlic and thyme. Reduce heat; simmer for 5 minutes. In the same small bowl, combine cornstarch and water until smooth; gradually whisk into raspberry juice mixture. Stir hot mixture until smooth and is thickened. In a large skillet, heat oil and butter over medium-high heat. Add the chicken; cook thoroughly. Pour sauce over meat to coat and serve immediately. Sprinkle with additional raspberries if desired.