Apple Filling / Topping

When I make pancakes for dinner, I like to make some kind of special sauce to go along with them.  This apple creation could be used for this, though I made it to function as the filling for a cake.  It has a nice taste of apple and it isn't too sweet, which makes it a winner in my book.  A nice bonus is that it also makes a very tasty "glue" in a layer cake.

Makes about 1 1/2 cups

2/3 cup sugar
1 1/2 tablespoons cornstarch
1 cup water
1 teaspoon cinnamon
1 Granny Smith apple, skinned, cored and finely chopped (about 1 cup)
1 tablespoon lemon juice

1. In small saucepan, mix sugar and cornstarch until cornstarch is no longer clumped.  Stir in water and mix until cornstarch is dissolved.  Stir in cinnamon.  Place saucepan on medium heat.  Cook and stir mixture until it bubbles and becomes clear.  Add apple pieces.  Return mixture to a boil to lightly cook apple.  Remove from heat, then stir in lemon juice.  If using as a sauce, use hot.  If using as cake filling, refrigerate filling until you are ready to use it.