Place a long column of ice in a highball glass. Add to this the Campari and soda water. Add the other ingredients to a shaker, seal and shake without ice. Add ice to the shaker and shake to chill, then strain into the highball glass to float over the Campari and soda mixture. Garnish with twists of lemon and orange peel. Serve with straw.
This drink is named for Pouring Ribbons' location, one flight of stairs up from a generic liquor store on Avenue B in Manhattan. The cocktail plays with the name through its two layer structure; imbibers can either consume the two parts separately or mix them to taste.