In reply to Steph-in-the-West:
toast one side, warm the other side, lashings of butter, first the sliced tomatoes (or branston pickle) then the davidstow, then mixed herbs, oojjiii......drip,dribble....
....and this works on jkt potatoe as well, mix tuna (tinned in brine and drain) with mayo,chopped peppers and onion and black pepper, put ontop of toast/jkt spud and then the davidstow....off to get me bib....