Cut the beef into bite-sized pieces.
Thinly slice the onion.
Place the rice in a bowl.
Add oil to a pan and cook the beef.
When the beef is cooked, add the onion and stir-fry.
Add the sauce (soy sauce, sweetener, mirin, etc.) and mix well.
Place the cooked beef and onion over the rice.
Top with a soft-boiled egg and chopped green onions as desired.