To prepare the walnuts, place in a non-stick skillet, add the maple syrup, a pinch of salt and stir for then put aside.
To prepare the dressing, squeeze 1 lemon in a large salad bowl, add grape seed oil, pear juice, white wine vinegar, a pinch of salt and a pinch of caster sugar. Whisk to combine the ingredients.
To combine the salad, add the butter lettuce leaves to the same bowl (after washing and draining the leaves). Mix to cover the leaves with dressing.
Grate some shaved fennel and shaved pear to taste then mix again to combine well. Top the salad with the maple walnuts halves and some freshly grated Pecorino cheese.