Pour the Campari and sweet vermouth into an ice-filled glass and stir. Top with Prosecco, garnish with orange peel, and serve.
In Italian, "sbagliato" means "wrong," "messed up," or "mistaken." The twist on the classic cocktail is said to have originated when a rushed bartender making a Negroni accidentally picked up a bottle of Prosecco instead of gin. A fortunate mistake, if you ask anyone who's tried it. A classic Negroni is equal parts gin, Campari, and sweet vermouth, but feel free to add a bit more Prosecco than you would gin, if you like. I've never seen a bartender in Italy measure a Negroni, so you'll be in good company.
Recipe courtesy of Julie Myers, Food52