Jack Rudy Small-Batch Tonic, Charleston.
$16-$19 for 17-ounce bottle, available at Reid’s Fine Foods.
Gin-and-tonics have taken a turn for the better since real quinine tonics, with depth and sweetness, have been bubbling up in bottle shops. Jack Rudy, named for Charleston mixologist Brooks Reitz’s great-grandfather, is a concentrate you top with sparkling water (or sparkling wine, for a twist on the French 75), so it goes a long way. The flavor is a revelation: quinine’s bite with notes of orange and lemon grass. Consider it a summer survival kit.