Sweet and Sour Chicken

This recipe is one that my husband loves from his childhood. Of course every time we make it we have to do something a little differently. This time we added onions, which apparently aren't in the original recipe, but the sauce base is really delicious. You could actually add a number of different ingredients and it would be great. The original recipe says that the recipe is also really good with pureed peaches or apricots, although I have never tried either of those things.

 1 can pineapple (with juice)
1/2 cup brown sugar
1/4 cup vinegar
1 tsp salt
1 green sweet pepper, chopped
1 medium onion, chopped
2 tomatoes, chopped (a can of diced tomatoes would also work)
1/4 cup corn starch
1 lb chicken, pork, or meatballs
salt and pepper to taste

Mix all ingredients except corn starch in a medium pan. Cook until peppers are tender. Mix corn starch with a tiny bit of cold water and add to sauce. Stir until it has thickened.