1 c. flour
2 tbsp. sugar
1/2 c. butter
1 tbsp. white vinegar

FILLING:

1/3 c. sugar
1 tbsp. flour
1/2 tsp. cinnamon
5 c. blueberries
Confectioners' sugar

Mix flour and sugar; cut in butter. Sprinkle with vinegar and press 1/4 inch thick over bottom and sides of 8 inch springform.

Mix sugar, flour and cinnamon in bowl. Add 3 cups berries and toss spoon into crust. Bake 50-60 minutes in 400 degree oven with oven rack in lowest position. Remove to cake rack and while hot sprinkle with remaining berries. Cool. Sprinkle with confectioners' sugar.