Prepare the vegetables: trim and cut the Broccoli and Cauliflower into bite-sized florets, slice the Carrot on the diagonal, halve the Baby Corn if large, remove strings from and trim the Snow Peas, slice the Shiitake Mushrooms, and thinly slice the Napa Cabbage; mince the Garlic.
In a small bowl mix the sauce: combine 1½–2 tbsp Oyster Sauce, 1 tsp Fish Sauce, 1 tbsp Light Soy Sauce, 1 tsp Sugar, 2–3 tbsp Water and a pinch of White Pepper; stir until the sugar dissolves.
Heat a wok or large skillet over high heat until very hot, then add 1–2 tbsp Vegetable Oil.
Add the minced garlic and stir-fry for about 15–30 seconds until fragrant, then add the carrots, broccoli and cauliflower and stir-fry for 2–3 minutes to start cooking the firmer vegetables.
Add the baby corn and shiitake mushrooms and continue stir-frying for another 1–2 minutes.
Toss in the snow peas and napa cabbage and stir-fry briefly until all vegetables are crisp-tender, about 1–2 minutes more.
Pour in the sauce, toss everything to coat and cook for 30–60 seconds until the sauce slightly thickens and glazes the vegetables; taste and adjust seasoning with more light soy or fish sauce if needed.
Serve hot with steamed rice or noodles as a side or light main.
