In a large mixing bowl, cream the butter and sugar with an electric mixer until light and fluffy. Add the egg yolks, potatoes, nuts, and spices, blend well. In a separate bowl, combine the flour and baking powder. Alternately add flour mixture and milk to creamed mixture, blend well. In a small bowl, beat egg whites with electric mixer until stiff peaks form. Gently fold egg whites into batter. Pour the batter into a greased and floured 9 x 13 inch baking pan. Bake in a preheated 350ºF. oven for 45 minutes or until a toothpick inserted into the center comes out clean.
Makes one 9 x 13 inch cake.

Potato Chocolate Cake 2

1 cup of softened oleo
2 cups of sugar
2 large eggs
Two 1 ounce squares of unsweetened chocolate, melted and cooled
1 cup of  plain mashed potatoes
2 teaspoons of vanilla
2 cups of unsifted flour
2 teaspoons of baking powder
1 teaspoon of salt
1/2 cup of milk

Preheat oven to 325ºF. Grease 13 x 9 inch pan. In large bowl on high speed, beat oleo until fluffy. Gradually beat in sugar until mixture is light. Add eggs, one at a time, beating well after each. Beat in chocolate, potatoes and vanilla. On a sheet of waxed paper, combine flour, baking powder and salt to potato mixture; add a quarter of the flour mixture and a third of milk; continue to alternate beating lightly until all flour mixture and milk have been added. Pour butter into prepared pan; bake 30 minutes or until cake tester inserted in center comes out clean. Cook cake in pan on wire rack. If desired, using fine sieve, sift confectioners sugar over cake before serving. Makes 20 servings. 

Irish Potato Cake 3

3/4 cup of butter or margarine
2 cups of white sugar
4 eggs
2 cups of sifted self rising flour
1 teaspoon of cinnamon
3/4 teaspoon of allspice
1 teaspoon of nutmeg
1/2 cup of milk
1 cup of mashed potatoes
1 cup of seedless raisins
1 cup of English walnuts or pecans, coarsely chopped
1 teaspoon of vanilla

Cream butter until soft and smooth. Gradually add sugar, beating until light and fluffy. Add eggs, one at a time, beating thoroughly after each addition. Sift together flour and spices. Add alternately with milk to butter mixture, beating until smooth after each addition (do not over beat). Stir in potatoes, raisins, nuts and vanilla until evenly blended. Pour into four greased 9" cake pans. Bake at 350ºF. for about 25 minutes or until done. Cool. Spread a thin layer of your favorite chocolate or lemon icing between each layer and on the top and sides of cake. 

Sweet Potato Cake 4

1/2 cup of shortening
1 1/3 cup of sugar
3 eggs
1 medium size sweet potato (already baked)
2/3 cup of buttermilk
1 3/4 cup of cake flour
1 teaspoon of soda
1 teaspoon of salt
2 teaspoons of cinnamon
1/2 teaspoon of nutmeg
1 cup of nuts

Cream shortening and sugar. Add eggs one at a time, beating well after each. Combine cooled sweet potato that has been mashed with buttermilk. Sift together flour, soda, salt, cinnamon and nutmeg. Add to creamed mixture alternating with potato mixture, beating well after each. Then add chopped nuts. Bake in greased and lightly floured pan at 325-350ºF. for 40-45 minutes or until fork comes out clean. Frost with butter cream frosting or with cream cheese frosting. 

Sweet Potato Pound Cake 5

1 cup of butter
2 cups of sugar
2 1/2 cups of mashed cooked sweet potatoes
4 eggs
3 cups of flour
1/4 teaspoon of soda
1/2 teaspoon of nutmeg
1 teaspoon of cinnamon
1 teaspoon of vanilla
1/2 cup of chopped pecans
1/2 cup of flaked coconut

Cream butter and sugar; add sweet potatoes and beat until light and fluffy. Add eggs one at a time beating well after each. Combine dry ingredients and stir into creamed mixture; add vanilla, nuts, and coconut. Pour mixture into greased 10 inch tube pan and bake at 350ºF. for 1 hour and 15 minutes or until cake tests done. Spread with icing while warm.

SWEET POTATO POUND CAKE ICING:
1 pound box of box confectioners sugar
Grated rind of 1 orange
Grated rind of 1 lemon
Juice of 1 lemon
Juice of 1 orange

Combine all ingredients, slowly adding enough orange juice to make spreading consistency.