In a medium mixing bowl, stir together flour, 1/2 cup sugar, 2 Tbsp cocoa powder, baking powder, and xanthan gum. Add milk of choice, oil, and vanilla; stir until smooth. Transfer batter to an ungreased one quart baking dish.
Combine the remaining 4 Tbsp cocoa powder and the 2/3 cup sugar. Gradually whisk in boiling water. Pour evenly over batter. Bake in a 350 °F oven for about 30 minutes or until cake is set. Serve warm.
Optional: Add 4 tsp instant coffee granules with boiling water for a mocha cake.
Notes
This is an old family favorite recipe that I created when we became gluten free. It is an easy, yummy dessert to impress anyone.
Substitutions
I use almond milk for this, but any should work fine.
I use olive oil, but use whatever oil is safe for your allergens.
Corn Substitutions: Corn is a common ingredient in products. Starch, modified food starch, dextrin and maltodextrin can be from corn. Consult with your physician to find out which corn derivatives you need to avoid. Many corn-free options are available in the US. Find out more about corn substitutions.
Gluten: Gluten is a protein found in specific grains (wheat, spelt, kamut, barley, rye). Other grains are naturally gluten-free but may have cross-contact with gluten-containing grains. Look for certified gluten-free products if you need to avoid gluten. Find out more about wheat and gluten substitutions.
Milk and Soy Substitutions: Alternative dairy-free milk beverages and products will work in most recipes. Find out more about milk substitutions and soy substitutions.