Shrubs are vinegar-based fruit syrups that can either be used as a juice concentrate (mixed with soda water) or mixed into cocktails to complement and enhance spirits. This is one of my favorite versions, as the natural pulpiness of the peaches makes the final product really thick and luscious. This shrub pairs well with most white spirits, from moonshine to light rum. For a simple shrub-based cocktail, mix equal parts spirit, shrub, and soda water with a dash of bitters.
Put the peach chunks in a bowl and, with a potato masher or your fingers, mash into a chunky paste. You should have 11⁄2 cups mashed peaches. Mix the sugar into the peaches. Don’t be afraid to be rough with it; the solids are later discarded, so you want to extract as much juice and pulp as possible. Cover the bowl with plastic wrap and refrigerate overnight.
Press the peach mixture through a fine-mesh sieve into a clean bowl, pressing hard on the solids to extract as much juice and pulp as possible. Discard any pulp trapped by the sieve. Whisk in the vinegar, then transfer to a mason jar or bottle with a tight- fitting lid and refrigerate for 5 days, shaking periodically to dissolve the sugar. The shrub will keep, refrigerated, for up to 3 months.