Which cocktail adds bitters on top of a sugar cube?

The Bellini is a beautiful refreshing drink that is low in alcohol and is really closer to drinking wine. No spirits touch these drinks and, yet, they’re still considered cocktails. 

The Champagne cocktail adds another dimension to a great glass of Champagne with the introduction of some bitters on top of a sugar cube that is dropped into the Champagne, suddenly turning it into a bitters and soda-style drink. Just much fancier.