1 c. sour cream
2 tbsp. flour
3/4 c. sugar
1 tsp. vanilla
1/4 tsp. salt
1 egg, beaten
2 1/2 c. blueberries
3 tbsp. flour
3 tbsp. butter, softened
3 tbsp. chopped nuts
1 graham cracker crust

Combine first 6 ingredients. Beat 5 minutes at medium speed of an electric mixer or until smooth. Fold in blueberries. Pour filling into crust shell. Bake at 400 degrees for 25 minutes. Combine remaining ingredients, stirring well. Sprinkle over top of pie. Bake 10 additional minutes. Chill before serving.