Contest-Winning Moist Chocolate Cake

In a large bowl, combine the first 6 ingredients. Add the eggs, coffee, buttermilk, oil and vanilla; beat on medium speed for 2 minutes (batter will be thin). Pour into a greased and floured 10-in. fluted tube pan., Bake at 350° for 45-50 minutes or until a toothpick inserted in the center comes out clean. Cool for 10 minutes before removing from pan to a wire rack to cool completely. Dust with confectioners' sugar.