Quick Vegetable Stir Fry

Make the stir fry sauce. Combine all of the stir-fry sauce ingredients in a small saucepan and cook over medium heat until the sugar dissolves. Store or use immediately.
Stir one tablespoon of cornstarch with three tablespoons of cold water, and then set aside.
Divide the vegetables into two piles. One pile should have heartier, longer-cooking vegetables (broccoli, carrots, and mushrooms), and the other pile should have quicker-cooking vegetables (bell pepper, scallions, snow peas, and tomatoes).
Heat a large, heavy skillet or wok over high heat. Add 1 ½ tablespoons of high-heat oil, and then add the pile of heartier vegetables (broccoli, carrots, and mushrooms). Cook, stirring the vegetables around the pan, until they sweat and soften, about 3 minutes.
Throw in the remaining vegetables and continue to cook for another 2 to 3 minutes or until the vegetables are tender. If the pan needs more oil, add another tablespoon. (For reference, you are looking for the broccoli to be bright green and crisp-tender, the mushrooms to brown slightly and reduce in size, and the snow peas to be bright green and a little floppy.)
Pour in the stir fry sauce. Give the cornstarch mixture one more stir, and then slowly pour it into the stir fry. Stir everything around until the sauce thickens and sticks to the vegetables. Serve immediately.

Ingredient :

6 garlic cloves, minced
3 tablespoons minced fresh ginger (thumb-size piece of ginger)
1 cup chicken or vegetable stock
2 tablespoons dark soy sauce
2 tablespoons light soy sauce
2 tablespoons Shaoxing wine, substitute dry sherry or mirin, see notes
1 tablespoon toasted sesame oil
2 tablespoons sugar
1/4 to 1/2 teaspoon ground white pepper