Step 1

Preheat oven to 350°F. Grease and line a 9 x 13 pan with parchment paper.

Step 2

In a large bowl, whisk together sugar, cocoa powder, gluten free flour, baking soda, baking powder, and salt. In a separate bowl, whisk oil, eggs, and buttermilk.

Step 3

Pour the wet ingredients into the dry, whisking until no lumps remain. Pour in brewed coffee, mixing until just combined.

Step 4

Pour batter into prepared pans and bake for roughly 30 minutes, or until a knife inserted in the center of the cake comes out clean. Cool completely on a wire rack before frosting.

Step 5

To make the frosting, place all frosting ingredients in mixing bowl.  Beat slowly at first to incorporate and then beat on high speed for 1 minute. Scrape down the bowl and repeat until the frosting has lightened slightly and is fluffy.

Step 6

Frost cake, spreading the frosting evenly over the whole surface, using the back of a spoon to create big swirls. Top with sprinkles if desired and enjoy!