http://www.globalpost.com/dispatch/news/regions/americas/cuba/140624/california-cuisine-narsai-david-meets-cuba-organic ENLARGE Groceries in Havana. (Stringer/AFP/Getty Images) HAVANA — San Francisco restaurateur Narsai David is in food heaven as he wanders through the stalls at a large farmer’s market. “The papayas are much sweeter and fresher here,” he exclaimed. At another counter, his lips puckered as he tasted a hot pepper. David is meeting with…