A handful of blackberries
1 ½ oz gin
1 oz fresh lime juice
½ oz grape hyacinth simple syrup
¼ oz grenadine
2 dashes grapefruit bitters
Fever tree sparkling lime-yuzu, to top
Muddle blackberries in a cocktail shaker lime juice. Add the rest of the ingredients except the sparkling lime-yuzu along with ice, shake to combine. Fine strain into a cocktail glass over fresh ice (and fresh blackberries), top with sparkling lime-yuzu. Garnish with a grape hyacinth.