1 c. softened butter
2 c. sugar
2 lg. eggs
2 (1 oz.) sq. unsweetened chocolate, melted and cooled
1 c. plain mashed potatoes.
2 tsp. vanilla
2 c. unsifted flour
2 tsp. baking powder
1 tsp. salt
1/2 c. milk

Preheat oven to 325 degrees. Grease 13 x 9 inch pan. In large bowl on high speed, beat butter 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.