Blueberries 'N' Cream Cheesecake 21/2 cups fresh blueberries 1 Tbsp. cornstarch 3 (8-oz) packages cream cheese, softened 1 cup sugar 5 eggs 2 Tbsp. cornstarch 1/4 tsp. salt 11/2 cups sour cream 2 Tbsp.sugar 1/2 tsp. vanilla 1/4 cup sugar 1 cup fresh blueberries   Combine 21/2 cups blueberries and 1 Tbsp.cornstarch in blender until smooth.  Cook in saucepan over med. - high heat about 15 min. or until slightly thickened,  stirring constantly.  Set aside to cool.  Reserve1/2 cup for glaze.   Beat cream cheese until light and fluffy.  Gradually add 1 cup sugar, mixing well.  Add eggs, one at a time, beating well after each.  Stir in 2 Tbsp. cornstatch and salt.  Pour batter into a greased 9-inch springform pan.  Pour first mixture over cheesecake batter;  gently swril with knife.                Bake at 325 for 45 min. or until set.  Remove from oven;  cool on wire rack 20 min.   Combine sour cream, 2 Tbs. sugar and vanilla in small bowl;  mix well.  Spread sour cream mixture over cheesecake.  Bake at 325 an additional 10 min.  Cool on wire rack.  Cover and chill 8 hours.   Combine reserved 1/2 cup first mixture, 1/4 cup sugar, and water in a small saucepan;  cook over med. heat stirring constantly, until thickened; let cool.  Gently fold in 1 cup blueberries;  let cool.   Remove sides of  springform pan.  spoon blueberry glaze on cheesecake.                        yield;  10 to 12 servings