Pineapple-Ginger Chicken Bake

From "Make-Ahead Meals Foodsaver Cookbook" by Jyl Steinback
Serves 12

Ingredients
3 cups sugar
1/2 cup + 1 tbsp. cornstarch
1 1/2 cups apple cider vinegar
3-8 oz. cans pineapple chunks, undrained
3/4 cup lite soy sauce
1 1/2 tsp. minced garlic.
1 1/2 tsp. ground ginger
2 1/2 lbs. boneless, skinless chicken breasts, cooked and cubed
3 cups sliced mushrooms
3- 8 oz. cans sliced water chestnuts, drained
6 cups frozen diced celery and onions

Directions
Combine sugar, cornstarch,vinegar, reserved pineapple juice, soy sauce, garlic and ginger in a large pot. Bring to a boil over medium-high heat; reduce heat to low and simmer, stirring frequently, until thickened. Combine chicken, mushrooms, waterchestnuts, celery and onions in large bowl and mix well. Pour sauce over chicken mixture and toss. Cool to room temperature and freeze.

To serve: Thaw overnight in refrigerator. Preheat oven to 350 degrees. Spray 2 baking dishes with cooking spray. Divide chicken mixture and bake, uncovered, 35-45 minutes until bubbly hot. Serve over cooked rice.