In large pot boiling salted water, cook beans until crisp-tender, about 4 minutes. Drain and rinse in colander under cold water then pat dry (can be prepared up to 1 day ahead and refrigerated, wrapped in paper towels, in plastic bags).
In 12-inch heavy skillet over moderate heat, heat butter until hot but not smoking. Add ginger and sauté until softened and fragrant, about 30 seconds. Stir in green beans and stock and cook, stirring often, until liquid is almost completely evaporated, about 3 to 6 minutes. Before serving stir in Cashews to distribute then transfer to serving dish and serve immediately .