Cobbled together from ricotta and greens, these dumplings have long evoked rustic Italian cooking. Yet precision is required to get their pillowy texture just right. Pillowy, verdant, milky-rich gnudi are Italian dumplings cobbled together from ricotta and greens (usually fresh spinach or chard), delicately seasoned, and bound with egg and flour and/or bread crumbs. The trick to making them well is water management: Both the cheese and the greens are loaded with moisture, much of which needs…