1/2 c. sugar
1/2 c. vinegar
2 tbsp. soy sauce
2 tbsp. sherry
3 tbsp. catsup
2 tbsp. cornstarch, dissolved in 1/2 c. pineapple juice (add last)

Cook all but cornstarch and pineapple juice over medium heat until sugar dissolves. Then add cornstarch and pineapple juice to thicken.