Lamprey and the wound it made. Sea lamprey feeding off a lake trout. Chef Bennett says the slimy mucus coating will practically melt away after this blanching. Though a knife will often be all that's needed to scrape it away, as a bit of extra insurance you can remove any remaining vestiges by rubbing the skin with a rough cloth. Open bronchial holes on the side of the fish and allow the blood to empty into the bowl.
Some recipes call for using lamprey blood.
If yours does, wash the lamprey with a cup or so of red wine, then mix this wine with the vinegar and blood, making sure that the latter doesn't start to coagulate. Rinse the fish again and then decapitate it by slicing around the body and pulling off the head. If you don't want crunchy lamprey, make sure the thick, bony cartilage comes out with the head. 2 cups fortified veal stock 1 bay leaf 2 tbsp. Add lamprey and vegetables, then sear until vegetables are tender.