Preheat Oven to 350*. Grease or Line (with unbleached parchment paper) two 8 or 9 inch round pans, or 1 13x9 pan. Mix Flour, xanthan gum, cocoa, baking soda, and salt together in a large mixing bowl. Stir in remaining ingredients and mix (by hand) until combined. Pour into pans and bake for 35-40 minutes, or until a toothpick inserted in the center comes out clean.
Cool completely before removing from pans. Frost with your choice of frosting.