"This is a very good cake and well worth the while. In the fall we love to walk in the woods and pick up the butternuts that fall from the trees - we have to fight with the squirrels to get them. I often replace this with pecans or walnuts when I cannot get them."
Preheat oven to 350 degrees F (175 degrees C). Grease a 9 inch tube pan. Sprinkle the bottom and halfway up the sides of the pan evenly with finely chopped butternuts (pecans or walnuts).
Sift together cake flour, baking soda, cinnamon, allspice, nutmeg, and salt. Cream the butter. Blend in lightly packed brown sugar and beat until light and fluffy. Beat in eggs. Stir dry ingredients into creamed mixture alternately with buttermilk. Blend in the finely chopped butternuts or pecans or walnuts.
Put gently into baking pan. Bake for 45 to 50 minutes, or until cake springs back when you touch it lightly. Cool in pan for about 10 minutes. Put on cake rack to cool completely. Leave upside down and sprinkle with confectioners' sugar over cake before serving.