Mix together the leek mixture, the cod and half the garlic cream.
Heat this mixture and stuff the potatoes with it. Place a belly on each potato, add a few grains of mignonette. Serve with the rest of the garlic cream.
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Mornay Sauce
Heat 50 cl of béchamel. Off the heat, add 2 beaten egg yolks with, if necessary, a little cream. Reheat for a few seconds. Stir in 70 g of sifted grated Gruyère without whisking.