If you are preparing several glasses, make the gin base in advance and keep it well chilled until you are ready.
½ measure gin
1 measure orange juice
1 slice peach
1 ice cube
1 slice of peach, to decorate
1. Whizz all except the champagne in a blender until smooth, about 10 seconds.
2. Pour into a flute and top up with champagne when ready.
3. Finish with a slice of peach.