STEP 1/6
Slice onions, green onions, and red peppers thinly, chop garlic thinly, cut saesongi mushrooms into squares 2cm apart in all directions, and cut off the bottom of oyster mushrooms.
STEP 4/6
Stir-fry onions, mushrooms, and garlic in a meat-roasting pan and add beef (sirloin) and steak sauce when onions start to become transparent.
STEP 6/6
Put the beef mushroom steak on a plate, put the chopped green onions and red peppers, and sprinkle balsamic sauce and sesame seeds to suit your taste.