Cut the oranges, grapefruit and lime into eighths. Halve the vanilla pod lengthways and unfold. Put together with all other ingredients in a large, sealable glass vessel (at least 2 l volume) and stir well.
Store in a dark and cool place for four weeks, turning occasionally. Then pour through a sieve, fill into bottles and enjoy cool. Makes about 1.5 liters of liqueur.
In Italy it is drunk as a digestif from a shot glass, the local name is Liquore di vino bianco all’arancia. Of course, you can also only use juice oranges and less vanilla, it`s a matter of taste.