Preheat your oven to 350°F (175°C). Grease and line two 9-inch round cake pans.
In a large bowl, sift together the flour, sugar, cocoa powder, baking soda, baking powder, and salt.
Add eggs, buttermilk, oil, and vanilla extract. Mix until well combined.
Stir in boiling water (the batter will be thin).
Divide the batter evenly between the pans and bake for 30-35 minutes. Cool the cakes completely.