Mix the tapioca flour with water to make the flour slurry until completely dissolved. Leave it aside.
Add light soy sauce, sesame oil, salt, pepper, and sugar to the water and mix until well-combined. Leave it aside.
Place a clay pot over the stove and let it warm up for about 2 minutes over medium-high heat, or until it radiates heat. Test it by hovering your hand in the clay pot without touching it.
Add the cooking oil and minced garlic. Stir fry for about 1.5 minutes, or until fragrant and golden brown. Remove most of the garlic and place it in a heat-resistant bowl. Leave it aside.
Reduce the heat to low. Wash the mushrooms briefly under running water. Add all the prepared vegetables - carrots, green peas, shiitake mushrooms, baby corn, tomatoes, white shimeiji mushooms, Chinese cabbage, and fried tofu.
Pour the mixed seasonings all over the vegetables. Carefully cover the clay pot, and braise them for 8 minutes over high heat.
After 8 minutes, with heat-resistant gloves, or wet, thick, kitchen towels, open the clay pot cover carefully.
Stir to rotate the vegetables around. Cover the clay pot and braise for 2 more minutes.
After 2 minutes, open the cover. Carefully taste and adjust (optional).
Pour the flour slurry and immediately stir carefully to thicken the gravy. Switch off the heat.
Pour the crispy garlic with oil all over the gravy. Stir the gravy a little to mix in all the garlic and oil. Cover the clay pot and set it on a heat-proof coaster with heat-resistant gloves, or wet, thick cloth.
Serve with rice, or enjoy as-is while warm.