Cream butter and sugar. Add eggs and buttermilk and beat until creamy.
Sift flour, soda, salt and spices together. Add to creamy mixture. Add prunes (don't cut these up any more than necessary to pit them) and chopped nuts. Mix well.
Bake in 2 greased and floured 9" layer-cake pans for 30 minutes in a preheated 375° oven.
Cool layers in the pans on a rack for a few minutes. Remove from pans, cool completely and frost with Almond-Cider Frosting, White Frosting, or Fruit Frosting.