In a Dutch oven, heat the lard over high heat and add the onion and leeks. Cook over high heat until softened and browned, about 5 minutes. Season the guinea hen pieces with salt and pepper and place in the pot. Sprinkle the meat with the flour and cook until the meat is well browned. Add the wine, grappa, and nutmeg and bring to a boil. Reduce to a simmer and cook until the meat is cooked through, about 30 minutes. Remove the meat from the pot and keep hot. Add the mushrooms, potatoes, and sausage and cook for an additional 15 minutes, then stir in the butter, return the meat to the pan to heat through and serve with the sauce drizzled over.
Recipe copyright 2001, Mario Batali. All Rights Reserved.