Ma Po Tofu, a classic dish from the Sichuan province of China, inspired this recipe. The original is made with soft tofu and ground pork or beef with plenty of heat from dried chile peppers and Sichuan peppercorns. Portobello mushrooms stand in for the meat in our vegetarian version and convenient jarred chile-garlic sauce gives it plenty of kick. Serve with brown rice.
Heat oil in a large saucepan over medium heat. Add garlic and ginger and cook, stirring, until fragrant, about 30 seconds. Add mushrooms and chile-garlic sauce and cook, stirring occasionally, until most of the mushroom liquid has evaporated, 4 to 6 minutes.
Add broth, sherry, soy sauce, brown sugar, tofu and water chestnuts and bring to a simmer. Cook, stirring occasionally and adjusting the heat as necessary to maintain a simmer, for 10 minutes to blend flavors.
Combine water and cornstarch in a small bowl. Stir the mixture into the saucepan and simmer until the sauce is thickened, about 2 minutes.