Combine soy sauce, water, garlic, ginger, oyster sauce, sugar and mix well. Set aside.
Heat a wok or frying pan then put-in the cooking oil.
When the cooking oil is hot enough, pour-in the sesame oil.
Stir fry the Bok Choy. Put the stalks first and stir fry for about 2 minutes then add the leaves and stir fry for 2 to 4 minutes.
Turn off the heat and transfer the cooked Bok Choy in a serving plate.
Heat the same wok or frying pan then pour-in the sauce mixture. Cook for about 2 minutes or until the sauce thickens.
Turn off heat then top the sauce over the Bok Choy.
Serve. Share and enjoy!