Preheat oven to 350 degrees.
Grease and flour the cake pans and then line the bottom of the pans with round parchment paper for easier removal.
Cream the butter and sugars in a large mixing bowl. Add in the eggs one at a time and blend with a handheld mixer.
Add in the vanilla and mix to combine.
Combine flour, baking soda, baking powder, salt and cocoa powder in a large bowl.
Alternating between the two, slowly add the dry ingredient mixture and beer to the bowl with the butter and sugar. Mix on low speed to combine ingredients.
Divide the cake batter evenly between the three cake pans.
Bake 22-28 minutes or until a toothpick inserted in the center of the cake comes out clean.
Cool and then remove the top of each cake with a cake leveler.
Mix the frosting by creaming the butter and powdered sugar.
Add in the vanilla and whiskey, missing with a hand-held mixer on low speed.
Spread icing across each layer of cake and stack.
Frost the top and sides of cake.