Parboil sausages until done (about 15 minutes). Reserve warm.
Wash potatoes. Boil or steam, skin on, 45 minutes or until done. Drain.
Mash potatoes by hand in hotel pan with half-and-half, salt and pepper. Reserve warm.
Grill sausages until brown, turning constantly, about 5 minutes
To serve: Plate 4 sausages with 4 oz. Scoop of mashed potatoes. Top with 2 1/2 oz. Mushroom gravy. Serve with mustard for dipping, and salad or vegetables.