In a wok or frying pan, heat the cooking oil to smoking point.
Spread the ground beef in the hot oil. Cook without disturbing for a minute or two then stir to break up large lumps.
Pour in the soy sauce. Sprinkle in two pinches of pepper. Stir fry until the mixture is quite dry.
Throw in the sliced onion and minced garlic. Stir fry for half a minute.
Add the sliced shiitake and julienned carrot. Sprinkle in a quarter teaspoon of salt and another pinch of pepper. Stir fry for half a minute.
Next, add the bok choy tips and stir.
Stir together all the ingredients for the sauce and pour into the pan. Cook, stirring, until the sauce is thick and clear. That should be just enough time to cook the bok choy tips through and still be lightly crisp.
Serve your ground beef, shiitake and bok choy tips stir fry over rice with split boiled eggs on the side.