Step 1: In a bowl, combine all the sauce ingredients and stir to evenly mix everything and attain a slightly thick sauce that looks like this.
Step 2: In a large pan or wok, heat about 2 tablespoons of vegetable oil and sauté garlic, followed by onion. Add the carrot when the onion is translucent.
Step 3: Continue cooking then add the celery when the carrot is cooked through, followed by the mushroom and green onions.
Step 4: When all veggies are already cooked, pour the sauce mixture. Continue cooking while stirring to have a smooth consistency. Cook until the sauce thickens. Transfer the sauce to a bowl and set aside.
Step 5: In the meantime cook the tofu. If you have sizzling plate, heat the plate in the stove until very hot that droplets of water will disappear in an instant.
Step 6: Add some oil and cook the tofu by slightly browning, first on one side then on the underside. Then pour the sauce to create that wonderful sizzling-smoking effect.