Braised Egg Tofu with Mushroom

I like this dish. Have been attempt re-create it a few times, and finally got quite close to the original dish.

Ingredients:
300g egg tofu (about 2 tubes)
one small canned mushroom (cut into smaller pieces)
a few slice of carrot
1 egg
spring onion for garnish (optional)

1 cup of water
2 tbsp of concentrated abalone stock (can use concentrated chicken stock)
1 tsp oyster sauce
1 tsp light soy sauce
1 tsp sesame oil
potato starch water(mix 1 tbsp potato starch with 2-3 tbsp water)

Method:
1. Slice the tofu into 1 cm thick pieces. Deep fried each side till golden. Set aside.
2. Pour water and concenrated abalone stock into wok, stir till combined, add in carrot and canned  
    mushrooms, add in tofu, oyster sauce, soy sauce, bring to boil.
3. Beat the egg in a bowl, slowly pour egg into wok, at the same time stir the content in the wok so as to
    break up the egg.
4. Add in potato starch water and thicken the content, lastly add in chopped spring onion and sesame oil.
    Server warm.