Recipe: Four-Way Citrus Shrub

From House of Angostura Ambassador, Rohan Massie:

This version of the lemon, lime and bitters is all about using waste ingredients. Here take the excess peels and husks from approximately one handful of waste citrus peels and husks. I used lemons, limes, grapefruits and orange but it can really be any citrus fruit you use at home. Combine with 500g sugar, give a light massage to get the oils flowing and leave covered overnight. The next day add 750ml hot water (approximately the temp you would drink tea at) and stir to dissolve sugar. Add 50 mls of Chardonnay vinegar to provide acidity.