Sunday afternoon cocktail: Scotch Crusta & a Gin, verjus, tarragon, lime concoction called a Spring Fling. The verjus is an unfermented white wine grape that tastes tart and acidic. Apparently, it’s a good ingredient to add when you want to add acidity without adding additional citrus. For instance, you could substitute limes for lemons, and add a little verjus to cut the sweetness. At Range in San Francisco.