Step 1

Begin by preheating oven to 350°F/175°C and grease and line three 6" inch or 2 8-inch cake pans.

Step 2

Add 2 2/3 cup gluten free flour, 2 cups sugar, 1 Tbsp baking powder, and 1 tsp salt into a large bowl and gently combine with a whisk.

Step 3

Make a well in the center of your dry ingredients and add 1 cup of water, 1 cup sour cream, 1/2 cup vegetable oil, 2 large eggs, and 1 Tbsp vanilla bean paste or vanilla extract. Gently whisk the wet ingredients together until they start to combine. Then slowly begin to mix them into the dry ingredients.

Step 4

Mix the batter for a couple minutes to help give the batter structure. You don't have to worry about over-mixing because there's no gluten in this batter!

Step 5

Cover and let the batter sit for about 30 minutes to give the gluten free flour time to absorb more of the liquid in the batter. This helps prevent the cake from having a gritty texture.

Step 6

Divide the batter evenly between the prepared cake pans and bake for 35-38 minutes, until a toothpick comes out with moist crumbs. I like to rotate my pans halfway through to help them bake more evenly.

Step 7

Let the cake layers cool in their pans for 10 minutes before flipping them onto wire racks to finish cooling.

Step 8

While the cake layers bake and cool, make the buttercream frosting.

Step 9

Beat 2 cups of butter on a medium speed for 30 seconds with a whisk or paddle attachment until smooth.

Step 10

Mix in 2 tsp vanilla bean paste or vanilla extract and 1/2 tsp salt on a low speed.

Step 11

Gradually mix in 7 cups powdered sugar and 3 Tbsp of heavy cream on a low speed.

Step 12

Beat on low until the ingredients are fully incorporated and the desired consistency is reached.  If the frosting seems too thick, add in additional cream (1 Tablespoon at a time). If the frosting is too thin, add in more powdered sugar (1/4 cup at a time).

Step 13

Stack and frost the cake layers, then decorate as desired.