This is such a great fruity but not-too-sweet summer cocktail. I saw the Bon App's Shrub Recipe and given my propensity for vinegar, I could resist. You can use any ripe summer fruit. I chose blackberries because they're Jamie's favorite. They were so light and delicious, and dangerous because you hardly taste the alcohol. Don't let the vinegar scare you. No one knew there was any vinegar in them until I told them how the cocktails were made. Can't wait to make them again, and try with another fruit! Maybe nectarines??