Preheat the oven to 350 degrees. Line the pan with cupcake liners.
Whisk the flour, cocoa powder, baking soda, baking powder, and salt in a bowl. Set aside.
Grab a different bowl and beat together the oil, vanilla, buttermilk, and sugars for 2 minutes. The sugar should dissolve showing that it's done being mixed.
Beat in the eggs and then add the flour mixture.
Add boiling water and beat together.
Add the batter to the liners 2/3 full.
Put in the oven and bake for 18-22 minutes.
To make the frosting, beat together the butter, icing sugar, and cocoa powder for 2 minutes.
Add the whipping cream, vanilla, and salt. Beat until it's thick and smooth and holds peaks.
You can add in more sugar, cocoa powder, or cream as needed.
Put the piping into a bag and add a tip. Frost the cupcakes and add sprinkles.