Peel the onion and garlic and dice very finely. Clean the mushrooms and cut in halves or quarters depending on the size.
In a non-stick pan, heat some clarified butter on high, setting 7 of 9. Fry the mushrooms in portions until they are golden yellow. All mushrooms should be in contact with the bottom of the pan in order to fry evenly. Just before the mushrooms are ready, add a little garlic and onion; Turn more often so that nothing burns. Season with salt and pepper and serve warm.
My tip: The mushrooms taste very good with grilled flank steaks or rack of lamb.