Preheat the oven to 350.
Beat margarine at medium speed with an electric mixer until creamy.
Gradually add sugar, beating well.
Add egg, orange juice, and vanilla.
In another bowl, combine flour, baking powder, and salt.
Add this to the margarine mixture.
Stir into a uniform dough.
Cover in plastic wrap and refrigerate: overnight is best but may be made two days ahead.
Roll out chilled dough on a lightly floured surface to ⅛ inch thickness.
Cut 3 inch circles with a cookie cutter or drinking glass.
Place a half a teaspoon of pie filling in the center of each circle.
Shape into a triangle.
Place hamantaschen one inch apart on baking sheet with parchment paper.
Use water to keep corners together.
Brush with egg white and sprinkle with cinnamon sugar.
Bake for 15 minutes.
