One of the several ways to cook tofu is with oyster sauce. best on a sizzle plate.

The other important ingredient in this recipe is oyster sauce. There are very many commercial vegetarian Oyster Sauce product on the market both online and in store. This will be one of the very few times that I would recommend a Google search for "Vegetarian Oyster Sauce". As mentioned there are many and I honestly wouldn't be able to summarise these or make a recommendation from the choies. There are variations as well so I really do suggest that you make a shortlist of choices, either go to your retail supplier of Asian foods or probably a large supermarket would carry some. If this isn't an option for you then check out the online suppliers. "Temple of Thai" and "Importfood.com" may carry these lines and both of these companies offer a good service and are reliable companies in my experience. If you are having trouble locating a brand or supplier I'm happy for you to drop me an email on the Contact page and I'll see what I can suggest.

Ingredients:
2 blocks of firm tofu

The sauce ingredients:
¼ cup oyster sauce,
¼ cup soy sauce,
2 cups broth,
2 tbsp brown sugar,
2 tbsp corn starch or corn flour,
½ tsp ground pepper 
1 tsp sesame oil.

Method (Sauce):
In a bowl, combine all the sauce ingredients and stir to evenly mix everything to make a slightly thick sauce.

The vegetable ingredients:
4 gloves garlic, peeled and minced,
1 pc large onion, peeled and minced,
1 pc small carrot, peeled and minced,
2 tbsp minced celery, stalk and leaves combined,
1 pc mild chili pepper, minced,
2 tbsp minced green onion leaves
½ to ¾ cup minced mushroom

Method:
In a large pan or wok, heat about 2 tbsp of vegetable oil and sauté garlic, followed by onion.
Add the carrot when the onion is translucent.
Add the celery when the carrot is cooked through, followed by the mushroom and green onions.
When all are cooked, pour in 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.
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.
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.

Serve sizzling.