Heat 3-4 tablespoons of olive oil in a large pan, peel the garlic cloves, press through and sauté. Then add the thinly sliced mushrooms to the pan, stir well so that the mushrooms are mixed with the garlic. Then squeeze half a lemon over the whole thing, add the peppercorns and bay leaves. The mushrooms then draw a lot of water and are steamed without a pan lid until the water has evaporated (approx. 30 minutes). Then put the mushrooms with the remaining ingredients in a mason jar, pour in enough olive oil until everything is covered and let cool.
The whole thing can be kept in the refrigerator for approx. 14 days and tastes best after a marinating time of 24 hours.