Cut the fillet into thin slices (like ham) using a machine, place them in a slightly overlapping wheel pattern on a serving dish. Mix the Condy Mì extra virgin olive oil with truffles, Lemondor lemon juice, finely chopped garlic, salt and pepper in a bowl.
Pour this sauce over the meat and marinate in the refrigerator for a couple of hours. When serving, cover with thinly sliced mushrooms.