Black Walnut Cake
["1/2 c. butter, softened", "1/2 c. shortening", "2 c. sugar", "5 eggs, separated", "1 c. buttermilk", "1 tsp. soda", "2 c. flour", "1 tsp. vanilla", "1 1/2 c. chopped black walnuts", "1/2 tsp. cream of tartar"]
["Cream butter and shortening.", "Gradually add sugar; beat well. Add egg yolks; beat well.", "Combine buttermilk and soda; stir well. Add flour to creamed mixture alternately with buttermilk.", "Stir in vanilla.", "Add the walnuts.", "Beat egg whites with cream of tartar until stiff peaks form.", "Fold in batter.", "Pour into 3 greased and floured pans.", "Bake at 350\u00b0 for 30 minutes.", "Cool 10 minutes in pans before removing."]
["butter", "shortening", "sugar", "eggs", "buttermilk", "soda", "flour", "vanilla", "black walnuts", "cream of tartar"]