Blackberry Custard Pie

Directions

1. 1
   Cook blackberries; add sugar and stir.
2. 2
   Add margarine and stir.
3. 3
   Mix 1/2 cup milk and flour, stirring until the mixture is not lumpy.
4. 4
   Combine blackberries and flour mixture and cook until done.
5. 5
   Pour mixture into pie shell.
6. 6
   Let cool, then top with 1 1/2 cups Cool Whip.