Step 1Cut the pork, veal and back fat into 1-inch cubes. Freeze the cubes in separate bowls for about 30 minutes to firm them up before grinding.
Step 2Grind the pork, veal and back fat separately through a meat grinder fitted with a three-eighths-inch grinding plate into a large bowl set over an ice bath.
Step 3Combine the meats and fat together with the pepper, salt, caraway seed, marjoram, allspice and sugar. Cover and freeze the mixture for 30 minutes. Remove and grind the mixture again using the finest grinding plate of the meat grinder. Add the heavy cream and mix well, using your hands.
Step 4Fry a small patty until done to check the flavor and seasoning (the sausage should be cooked to an internal temperature of 165 degrees). If necessary, adjust salt, pepper and other seasonings, then fry another small patty and check again.
Step 5Stuff the mixture into the prepared casing according to the manufacturer's instructions for your sausage stuffer. Prick any air pockets with a pin and twist off into 4- to 5-inch lengths. Refrigerate for up to 2 days, or freeze up to 2 months.