Preheat oven to 350F.
2 ½ cups rice flour
1 ½ cups white sugar (a diabetic could substitute Splenda)
2 Teaspoons baking soda
1 Teaspoon salt
2 ½ Teaspoons xanthan gum (1 teaspoon per cup of flour)
½ cup Hersheys Baking Cocoa Powder
2/3 cups canola oil
1 Tablespoon Vanilla
2 Cups of clear Soda (Sprite, 7-Up or the like, or cold coffee or water)
2 Tablespoons gluten-free white vinegar
Blend all the dry ingredients together in a 9 x 13 inch baking pan, add the wet ingredients, then the soda last. Stir (do not whip) until all of the dry ingredients are wet. Bake 35 to 40 minutes. Test for doneness by pressing on the center. Remove and let cool before frosting.
Optional: Dusting of powdered sugar.