- 1 (1 inch) piece ginger, peeled
- 3 cups homemade fish stock or thawed, frozen fish stock
- 1 large leek, cut into 1/4-inch-thick slices, well washed
- 3 star anise
- 3 tablespoons dry sherry
- 1 1/2 tablespoons low-sodium soy sauce
- 1 teaspoon canola oil
- 2 shallots, finely chopped
- 3 cloves garlic, minced
- 12 ounces white button mushrooms, cut into 1/4-inch-thick slices
- Salt and freshly ground black pepper
- 10 canned water chestnuts, cut crosswise into 1/4-inch-thick slices
- 1 head Chinese (napa) cabbage, cut crosswise into 1/2-inch-thick slices
- 6 scallions, thinly sliced on bias, plus more for garnish
- 6 (5 ounce) flounder fillets
- Thinly slice half the ginger; cut remaining half into 1 1/2-inch-long matchsticks, and reserve. Place sliced ginger, stock, leek, star anise, sherry, and soy sauce in a small saucepan. Bring to a boil. Reduce heat, and simmer 15 minutes. Strain and reserve stock.
- In a large, straight-sided saucepan, heat oil over medium-low heat. Add shallots and garlic; saute until translucent, about 5 minutes. Add mushrooms; season with pepper. Raise heat to medium high; cook until browned, about 7 minutes. Add water chestnuts, and cook 2 minutes. Transfer mixture to a bowl.
- Place cabbage and sliced scallions in saucepan. Season fillets with salt and pepper. Roll up fillets; place on cabbage. Add reserved fish stock and cooked vegetables. Bring to a boil. Cover. Reduce heat; simmer until fish has cooked through, about 15 minutes. Garnish with ginger matchsticks and scallions. Serve hot.