Clean the mushrooms: If they are very fresh, it might be enough to just wash them. I always peel off the skin to be on the safe side. Cut the mushrooms in half and fry them in a pan in about 4 table spoons of olive oil. Clean the garlic and stir in with the mushrooms as they are almost done. When all the water from the mushrooms has evaporated, add 1 tablespoon of balsamic vinegar and 1 table spoon of red wine vinegar, salt and pepper according to taste. Finally stir in the washed and chopped herbs, give them one minute of cooking and switch off the fire. Let the mushrooms cool down and store them at least one night in the fridge before serving.