Step 1

Preheat the oven to 350F. Coat 2 9-inch cake pans with cooking spray and set aside.

Step 2

In a large bowl, combine the flour, sugar, cocoa powder, baking soda, xanthan gum (if using), and salt.

Step 3

In a medium bowl, combine the milk, oil, vinegar, and vanilla.

Step 4

Pour the wet ingredients into the dry ingredients. Stir until smooth, scraping the bottom and sides of the bowl.

Step 5

Pour into greased cake pans and place in the preheated oven.

Step 6

Bake for 25 to 30 minutes, or until a toothpick inserted into the center comes out clean.

Step 7

Remove from the oven and transfer the cakes to a wire rack to cool completely.

Step 8

While the cakes are cooling, make the frosting.

Step 9

Frost the cake by placing one base layer on your plate or cake stand, spreading about a cup of frosting on top, top it with another cake layer, and spread remaining chocolate frosting over the top and sides.