Preheat oven to 350 degrees F
Butter and flour two 9" cake pans
Sift the unsweetened cocoa powder, all purpose flour, baking soda, baking powder, and salt, set aside.
In a separate bowl, combine the eggs, vegetable oil, milk, sugar, and vanilla extract.
Mix the flour mixture and egg mixture until well incorporated then pour in the boiling water slowly while mixing
Divide the batter evenly between the prepared pans and tap pans on the counter to get rid of any air bubbles
Bake the cakes for about 28-30 minutes or until fully cooked through
Allow the cakes to completely cool
To make the frosting, mix the unsalted butter until smooth then add the cocoa powder, powdered sugar, milk, and vanilla extract.
Mix on medium high speed for about 3-4 minutes or until nice and fluffy.
Frost the cooled cakes with the chocolate buttercream and enjoy