1oz Cointreau
.75oz Campari
.5oz Lemon Juice
Soda Water
Shake the first four ingredients with ice, double strain into an old fashioned with ice and top with soda water. Garnish with some lemon.
A more traditional way to serve this is in a Collins glass, leaving room for a few ounces of soda water. However, if you want something more bracing, bitter and sour -something more akin to an aperitif- just a splash of soda water is enough to open things up.