Graham Cracker Cake

2 pkg graham crackers
¼ lb butter
1 cup sugar
1 tsp vanilla
3 egg yolks
2 tsp baking powder
1 cup milk
walnuts
Cream together butter and sugar with vanilla and egg yolks. Roll out graham crackers adding baking powder, walnuts. Mix all ingredients together adding milk. Beat egg whites and gently fold into batter. Bake at 350 degrees for 20-30 minutes or until cake pulls away from edge. Top cake with frosting.