Cut the tofu into pieces and pat dry with paper towels
Heat up your wok or deep fryer and add oil. Deep fry the tofu until light to golden brown, dish out and drain with paper towel. Set aside.
Heat the oil a claypot over medium high heat
Add garlic and ginger. Cook for about 1 minute
Add mushrooms, carrots and cabbage. Cook and stir until the residual liquid from vegetables has mostly evaporated.
Add broth, soy sauce, sugar, firm tofu and water chestnutsto the wok.
Bring broth to a simmer, cooking for another 15 min.
Add corn starch mixture and 1 tsp sliced spring onion into the wok, bringing up the heat slightly to thicken the sauce.
Once sauce has thickened, remove from heat.
Once sauce has thickened, remove from heat. Garnish with chopped spring onion and serve hot with rice.