Preheat oven to 350 degrees. Mix all dry ingredients. Add oil and beat well. Add eggs one at a time and beat after each addition. Stir in grated carrots. Pour batter in two greased 9-inch cake pans and bake for one hour or until done. Cool for 10 minutes, remove layers from pans, and set on racks. Cool thoroughly before frosting.
For the frosting, beat butter and cream cheese together. Add sugar, vanilla and nuts. Beat well. Smooth over each layer (and around edges if you like, but I don’t). The frosting is very sweet so cutting up to a cup of the confectioners’ sugar won’t hurt it.