Carefully remove skin from goose neck so as not to damage it. Turn neck skin inside out and scrape away the fat. Return to original shape. Soak 1/2 cup bread crumbs in 1/2 cup milk. Run small piece of unsalted pork fat (slonina) (about 1/8 pound) through meat grinder with 4 ounces fresh, uncooked mushrooms and 1 raw goose liver.

Combine ground mixture with 1/4 pound raw ground veal and the soggy bread crumbs with excess moisture squeezed out. Mix well and run entire mixture through meat grinder again. Mix in 1 whole egg and season to taste with salt, pepper, and nutmeg. 

Fill goose-neck skin with mixture. Tie both ends with string like sausage, puncture in several places to prevent bursting during cooking, and place in pot with boiling salted water. Cook covered on low heat 1 hour. Slice and serve.