One of my favorite ways to use up the pork shoulder is to shred it and put the pork shoulder into shreds with BBQ sauce on a bun. Shred up into chili, soup, and even fried rice. Like any other meat ...
For the pork layer, finely chop the pork shoulder and pork belly ... Put in a roasting tin and add just enough boiled water to reach up to 2cm/¾in up the side of the terrine.
However, it's not always made with corned beef. They use all sorts of meat cuts. A boiled dinner typically includes corned beef, beef brisket, smoked pork shoulder, or ham shoulder boiled with cabbage ...