Cut the beef into thin slices, mix in the marinade and put in the fridge for 20-30 minutes
Give the mushrooms a quick rinse and wipe them dry. Cut each mushroom into 3-4 slices.
Cook the garlic on medium heat until it is fragrant. Change to high heat and put the beef in. Lay each piece flat with no overlapping then pan fry it until it changes color. Flip to the other side. Take it out when it is medium rare.
Add a small amount of oil then stir fry the mushrooms. When the mushrooms soften and begin to release water, turn to high heat and add the beef. Add in cooking wine, soy sauce, oyster sauce and water.
Add the black pepper in. Continue to stir fry until the sauce thickens.