6 Japanese eggplants or 1 large Italian eggplant
2 tsp. salt
4 Tbsp. peanut or corn oil
1 Tbsp. soy sauce
1 Tbsp. sugar
1/4 cup chicken stock
2 tsp. grated fresh peeled ginger
1 Tbsp. minced garlic
1/4 tsp. dried red chili flakes
1/4 cup chopped water chestnuts
3 green onions, trimmed and chopped
1 Tbsp. red wine vinegar
1 Tbsp. sesame oil
1 Tbsp. tasted black sesame seeds (for garnish)
Cut eggplant into 1/2-by-2-inch strips. If using Italian eggplants, peel skin. In a colander, toss eggplant with salt; drain for 30 minutes.
Squeeze gently to remove excess water. Pat dry with paper towels.
In a small bowl, mix soy sauce, sugar, and chicken stock. Preheat wok until hot over high heat. Add 3 Tbsp. oil and tilt wok to coat sides. When hot, add 1 layer of eggplant, stir-fry until seared and tender (about 3 minutes). Remove to colander. Drain over a bowl to catch juices. Cook remaining eggplant in same manner, adding more oil if needed. Reheat wok over medium-high heat. Add remaining 1 Tbsp. of the oil, ginger, garlic, and chili; cook gently but do not brown. Add water chestnuts and half of the green onions; stir-fry together for 5 seconds. Increase to high heat, add reserved soy sauce mixture and eggplant juices; bring to a boil. Return cooked eggplant; toss quickly over high heat until most of the sauce is reduced and absorbed into eggplant (about 1-to-2 minutes). Fold in vinegar and sesame oil.
Remove to serving dish. Top with remaining green onions and sesame seeds. Serve hot or cold.