there's only so much you can do with leeks & potatoes
i'm pretty sure its one of those cheffy terms (like 'jus' or 'reduction') that makes something very simple sound much fancier, more difficult & therefore easier to charge vast amounts of money for.
my bet is thats its spuds & leeks roughly mixed together & formed into a flat disc for the salmon to sit on top of
if its something different i'll eat my nage
