Add the thinly sliced beef and soy sauce to a pan. Cook until the beef releases its fat, then add the garlic, onion, and butter. Stir-fry everything together until fragrant.
Remove only the beef from the pan and set aside. Pour in the milk, then add the cheese and oyster sauce. Stir until the cheese melts into a smooth sauce.
Add the cooked rice and stir until the sauce becomes thick and creamy.
Transfer the rice to a plate, top with the reserved beef, and finish with a sprinkle of black pepper.
Korean-style creamy beef (woo-samgyeop) cheese rice bowl. Recipe via Han-kki-jip (saved from Instagram).