New Delhi, May 11 -- Come on, c'mon faster! You need to shake it really hard for the foam to form," says Kini Chacon as I work the cocktail shaker. Chacon is a chef at Rooftop Kitchen, a cooking class in Cusco in south-eastern Peru. Under her supervision, I'm getting a crash course in making Peru's national cocktail, the pisco sour. After nearly a minute of manoeuvring the shaker, I pour my cocktail into a glass and take it to the terrace. From the 10th floor of the building in suburban Cusco, I see the historic city spread out below me, its red-roofed houses and soaring church spires flanked by the verdant Andes. I take a sip of my cocktail, which is rather potent for a mid-day drink-but hey, it's five o'clock somewhere, right?

Over my ...