In a large bowl, cream sugar and butter until light and fluffy. Add eggs, one at a time, beating well after each addition. Stir together all dry ingredients; set aside. Combine cider and vanilla. Add dry ingredients alternately with cider mixture to batter. Mix until well blended. Spoon into a greased 10-in. angel food cake pan or fluted tube pan.
Bake at 325° for 1 hour 10 minutes or until a toothpick inserted in the center comes out clean.
Meanwhile, combine icing ingredients in a saucepan. Bring to a boil; reduce heat and simmer for 10 minutes. While cake is warm, drizzle half of icing over cake. Serve remaining icing over individual cake servings if desired.