I think I found the original of this in a Boke of Gode Cookery, but having looked at a lot of medieval pork-stuffed-with-pork recipes when planning this feast, I can’t remember.
5 lbs ground pork
1 ¼ c raisins
1 onion, diced
1T powdre forte
1 c pine nuts
⅓ c salt
25 lbs pork loin
Make a mix of the pork, raisins, onion, powdre forte, pine nuts, salt. Slice the pork loin lengthwise, then pound flat. Fill evenly with stuffing, then tie up and roast (covered!) for 2 hrs, basting occasionally
Leaves of Silk and Glass 