I made it for the last of the General Tso's Chicken I bought at Sam's. The package comes with sauce packets but I prefer homemade. Decided Sweet and Sour would be good. This recipe comes from Pei Mei's Chinese Cookbook, the most authentic Chinese CB in my collection.

3 tbsp vinegar
4 tbsp sugar
4 tbsp tomato catsup
4 tbsp cold water
3 tbsp cornstarch (start with ONE tbsp!)
1 tsp salt
1 tsp sesame oil (dark Asian type)

Stir constantly as you heat and let it thicken.