Score the duck breast skin with a sharp knife. Season with salt and pepper, and place, fat-side down, in a frying pan over a medium heat. As the fat begins to heat it will melt and crisp up. Continue to colour the skin for 10-12 mins before turning the duck over and frying for a further 4-5 mins to a pink stage. Remove the duck breasts to one side and keep warm.
Meanwhile, boil the maple syrup and simmer until just 2 tbsp are left before removing from the heat and whisking in the
sherry vinegar, groundnut and hazelnut oils. Season with salt and pepper.
While frying the duck breasts, trim and lightly rinse the wild mushrooms. When the duck is resting, fry the mushrooms in half the butter in a hot pan, seasoning with salt and pepper, until just tender. Heat a separate pan with the remaining butter and add the washed spinach. Season with salt and pepper, allowing the leaves to wilt and soften before draining.
To serve, divide the spinach among 4 plates. Cut each breast into 5-6 slices and place on top of the spinach. Top with the
pan-fried wild mushrooms, drizzling each with the maple syrup vinaigrette.