Raspberry Sour Cream Pie

Preheat oven to 400 degrees F (200 degrees C).
In a large bowl, beat eggs until light and lemon colored. Whisk in sour cream and vanilla. In a separate bowl, mix sugar, flour and salt together. Stir into egg mixture. Gently fold in raspberries. Divide into 2 unbaked pie crusts.
Bake in preheated oven for 30 to 35 minutes, or until the center begins to set. Sprinkle with topping and return to oven for 10 to 15 minutes, or until topping is golden brown. Allow to cool before serving.
To make the topping: In a medium bowl, mix together brown sugar, flour and chopped nuts. Cut in butter until crumbly.