Tofu and Leek Stir-Fry with Ground Beef

Preparation Wash leeks in a bowl of cold water, then lift out and drain well. Dissolve 1/2 teaspoon salt in 2 cups hot water in a medium bowl, and add tofu. Soak 5 minutes, then drain in a sieve. Heat a wok or 12-inch heavy skillet over high heat until a bead of water dropped onto cooking surface evaporates immediately. Add oil, swirling wok to coat, and heat until it begins to smoke. Add beef and stir-fry, breaking up lumps, until no longer pink, about 2 minutes. Stir in wine and 1/2 teaspoon soy sauce and stir-fry 30 seconds. Add chile bean sauce and stir-fry until fragrant, about 15 seconds. Add ginger, chile powder, and black beans and stir-fry until fragrant, about 30 seconds. Add broth, remaining 1/2 teaspoon soy sauce, and tofu, then reduce heat and simmer, stirring gently, about 2 minutes. Add leeks and simmer, stirring occasionally, until just tender, 2 to 3 minutes. Stir potato starch mixture and add to tofu, then cook, stirring, until sauce is thickened, about 1 minute.

Preparation Wash leeks in a bowl of cold water, then lift out and drain well. Dissolve 1/2 teaspoon salt in 2 cups hot water in a medium bowl, and add tofu. Soak 5 minutes, then drain in a sieve. Heat a wok or 12-inch heavy skillet over high heat until a bead of water dropped onto cooking surface evaporates immediately. Add oil, swirling wok to coat, and heat until it begins to smoke. Add beef and stir-fry, breaking up lumps, until no longer pink, about 2 minutes. Stir in wine and 1/2 teaspoon soy sauce and stir-fry 30 seconds. Add chile bean sauce and stir-fry until fragrant, about 15 seconds. Add ginger, chile powder, and black beans and stir-fry until fragrant, about 30 seconds. Add broth, remaining 1/2 teaspoon soy sauce, and tofu, then reduce heat and simmer, stirring gently, about 2 minutes. Add leeks and simmer, stirring occasionally, until just tender, 2 to 3 minutes. Stir potato starch mixture and add to tofu, then cook, stirring, until sauce is thickened, about 1 minute.