Juice of 1/2 lemon 1/4 lb. Gruyere cheese Salt and pepper Olive oil White truffles (optional)

Slice the mushrooms very thinly and immediately sprinkle them with lemon juice. Cut the Gruyere into the thinnest slices and then cut these into strips about 1 inch long by 1/4 inch wide. Sprinkle them over the mushrooms; season with salt and pepper and pour on a fine thread of the very best olive oil. Lastly, if you are in Italy, scatter on a few paper thin flakes of white truffle.