Mix together all the ingredients for the sauce in a small bowl.
Heat up the oil in wok or frying pan*.
Add the garlic and fry on a low heat for around 30 seconds, until fragrant and lightly browned - be very careful not to burn it!
Add the broccoli and pak choi and the sauce.
Cook on a medium heat for around 5 minutes, stirring regularly, until vegetables are cooked to your liking. I like to keep them slightly crunchy, but for more thoroughly cooked vegetables you can cook them for longer and cover the wok or frying pan with a lid.
Taste and add extra soy sauce (or tamari) if necessary.
Best enjoyed immediately!
*Using a wok will give a better flavour, but it's fine to make these in a frying pan. I used tenderstem broccoli and pak choi because that's what they use at Wagamama's, but you could use anything else like French beans, asparagus, cabbage, Brussels sprouts, kale, spinach, or whatever else you fancy.