Gluten-Free Sweet and Sour Sauce (GF)

I've been looking for a decent GF sweet and sour sauce recipe for a while, when I ran across this one through a fellow teacher. (Thank you Mrs. Howard!)

Ingredients:
1/2 cup sugar
2 Tbsp. corn starch
4 Tbsp. apple cider vinegar
1/4 cup ketchup
2 tsp. soy sauce (we use Tamari sauce--other brands are not GF)
20 oz. can pineapple

Directions:
Drain syrup off of a 20 oz. can of chunk pineapple. Add water to syrup to make 1 cup liquid. add all other ingredients. Cook on medium-low heat until mixture thickens. Stir constantly to avoid sticking.

This can be used over barbecued chicken as a baster. You can drizzle it over friend meats and veggies to make a rice topper. Whatever you prefer.