1 1/2 pounds Chinese or Japanese eggplants (about 3), trimmed, split into quarters lengthwise and cut into 3- to 4-inch lengths
2 red Thai bird chilies (or any small hot red chili)
3 tablespoons white vinegar or rice wine vinegar
2 tablespoons Shaoxing wine (or dry sherry)
1 tablespoon sugar
2 teaspoons soy sauce
1 tablespoon Chinkiang vinegar (use a not-too-fancy balsamic vinegar in its place if unavailable)
1 1/4 teaspoons cornstarch
3 tablespoons vegetable oil
4 teaspoons minced fresh ginger
4 medium cloves minced garlic (about 4 teaspoons)
4 scallions, whites thinly sliced, greens cut into 1/3-inch segments
2 tablespoons Sichuan chili broad bean paste (Doubanjiang)
Roughly chopped fresh cilantro leaves, for garnish
1. Combine 1/2 cup kosher salt with 2 quarts water in a medium bowl. Add eggplant pieces, skin-side up, and set aside to soak for at least 10 and up to 20 minutes.
2. Meanwhile, heat white vinegar in a small saucepan until simmering. Place sliced chilies in a small bowl and pour hot vinegar on top. Let rest for 5 minutes, then add wine, sugar, soy sauce, and Chinkiang vinegar. Stirring constantly, add corn starch and stir until dissolved. Set sauce aside. Drain eggplant carefully and pat dry with paper towels.
3. Heat oil in a wok over high heat until smoking. Reduce heat to medium add eggplant, and cook, tossing occasionally, until softened and well browned on all sides. Push to sides of wok. Return wok to high heat and add ginger, garlic, and scallions. Cook, stirring and tossing constantly, until fragrant and raw bite is gone, about 30 seconds. Add broad bean paste and cook, stirring for about 30 seconds. Pour in chili sauce, making sure to scrape in any sugar or starch that may have settled on the bottom.
4. Cook, tossing constantly, until sauce is thickened, glossy, and coats eggplants nicely, 1 to 3 minutes (if the sauce overthickens, thin with a few tablespoons of water). Transfer to a serving bowl, garnish with chopped fresh cilantro leaves, and serve immediately.