How to Make It
In a large bowl, mix the cornstarch with 1/2 teaspoon of salt. Add the scallops and toss to coat.
In a small bowl, mix the tangerine juice with the hoisin sauce, vinegar, soy sauce, brown sugar and chile-garlic paste. In another small bowl, combine the tangerine zest with the chopped garlic and ginger.
In a wok, heat 1 1/2 tablespoons of the oil over high heat until smoking. Add the scallops in a single layer and cook without stirring until they are golden on the bottom, about 3 minutes. Turn and cook until the scallops are firm, about 1 1/2 minutes longer. Transfer the scallops to a plate.
Add the remaining 1 1/2 tablespoons of oil to the wok along with the tangerine zest mixture and cook until fragrant, about 30 seconds. Add the zucchini, squash, carrot and water chestnuts and cook until the vegetables are crisp-tender, about 4 minutes. Stir the tangerine sauce and add it to the wok. Cook the sauce until slightly thickened, about 30 seconds. Return the scallops to the wok, stirring just until heated through, and serve.