What's an Italian farmer to do when life deals him extra lemons? Make limoncello, of course. In fact, distilling surplus fruit or grain to transform it into a potentially lucrative alcoholic beverage is an age-old strategy of farmers who have crops they otherwise can't sell at market. That was Sergio and Stefano Massa's solution when, in 1991, the brothers realized they'd have to let the lemons on their estate near the coastal city of Sorrento rot on the branch because the low market price didn't cover the cost of harvesting them. The Massas pulled out a hundred-year-old, beloved family recipe for the traditional Italian lemon-based digestivo, a liqueur that is often homemade and sold in small batches at farmers' markets along the Amalfi Coast. Today, nearly 20 years later, the production and sale of Villa Massa Limoncello ($26)—made with only sugar, water, molasses-based spirit, and the peels of fragrant and juicy Sorrento Oval lemons—help to support a thriving cooperative of lemon farmers on the Sorrentine peninsula. The clean, sweet, citrusy liqueur, so much more lively tasting than versions of limoncello made with additives, is lovely sipped cold and neat after dinner. You can also drizzle it over shaved ice for a cooling slushee. But I like it best mixed with two parts tonic water, served over ice, and garnished with a twist, for a terrific warm-weather refresher when I'm grilling outdoors.