Cut the excess fat off along the line of meat on the breast. Cut off the sinew as well. Place the breast skin side down on a griddle.

Clean the mushrooms carefully by just dabbing cold cold water over the cups of the mushrooms and towel drying them. Once dry, cut the cups up into large chunks. Cook the mushroom pieces in a little duck fat. Toss the mushrooms in this fat and season with salt and pepper. Turn the duck breasts on the griddle.

Add the shallots to the mushrooms and toss and cook for a further minute. Add the garlic then toss again. Leave the pan to one side. Place the green peppercorns in brine into a mortar and grind with a pestle to a paste. Rub the paste over the duck breast and leave to infuse before slicing.

Add the parsley to the mushrooms and toss to combine the flavours. Finally, add a little duck fat to the mushrooms and allow to stand before serving. Slice the duck and serve with the mushrooms.