Clean the enoki and king oyster mushrooms thoroughly and cut them into bite-sized pieces.
Slice the beef thinly and marinate it in bulgogi sauce for 10 minutes.
Heat cooking oil in a pan and stir-fry the beef.
When the beef is halfway cooked, add the enoki and king oyster mushrooms and stir-fry together.
Once everything is cooked, finish with black pepper and sesame oil to taste.