Cut the ribeye cap into bite-sized pieces.
Thinly slice the onion and green onion.
Heat cooking oil in a pan and stir-fry the ribeye cap.
Once the meat is cooked, add the onion and green onion, then stir-fry together.
Season with soy sauce, minced garlic, and pepper.
Continue stir-frying until all the ingredients are evenly cooked.