How to Make the Ultimate Umami-Bomb Vegetarian Demi-Glace
3/4 cup soy sauce
3/4 cup sake or dry sherry
3/4 cup mirin
2 tablespoons sugar
1 1/2 teaspoons finely grated lemon zest
1 1/2 teaspoons cornstarch
1 1/2 tablespoons fresh lemon juice
Vegetable oil, for the grill
Three 15-ounce blocks of extra-firm or firm tofu, drained and halved horizontally to form 6 slabs
3 tablespoons Asian sesame oil
3 tablespoons chopped scallion greens
1 1/2 tablespoons lightly toasted sesame seeds
In a small saucepan, combine the soy sauce, sake, mirin, sugar and lemon zest and bring to a boil. Simmer over low heat until fragrant, about 5 minutes.
In a small bowl, dissolve the cornstarch in the lemon juice. Whisk into the saucepan and bring to a boil, then cook over low heat for 1 minute, stirring. Let the teriyaki sauce cool.
Light a grill. Lightly oil the grate. Pat the tofu dry with paper towels. Place in a shallow baking dish and brush with the sesame oil. Grill the tofu over a medium-hot fire, basting with the teriyaki sauce, until heated through and browned, about 6 minutes. Transfer to a platter. Drizzle with the remaining sauce, sprinkle with the scallions and sesame seeds and serve.