Place vinegar, sugar, ketchup, and soy sauce in a small sauce pan over medium heat. Cook stirring occasionally, until sugar dissolves.
Mix cornstarch and water in a small bowl, and add it to the saucepan.
Continue stirring until mixture thickens. Remove from heat and add the pineapple juice.
Serve with your favorite appetizers, like these Crispy Pork Wontons or Crab Rangoons.
Notes
This recipe can easily be doubled or halved based on your needs.
This Sweet and Sour Sauce has a nice balance of sweet to sour. If you would like it sweeter, add more sugar. For more sour/tangy flavor add more vinegar.
If you do not have cornstarch, do not substitute arrowroot powder. It will turn into a gummy/gooey sauce. It will still taste good, but it is not as appetizing…trust me.