Cut winter melon into even strips. Cut tofu into small cubes.
Bring water to boil. Add sliced ginger, winter melon and mushroom. Season with salt, pepper, mushroom seasoning and brown sugar. Simmer until melon is tinder.
Add vegetarian shrimp chunks, sesame oil and black vinegar. Stir in potato starch (or corn starch) pre-mixed in water to thicken the soup. Add tofu. Bring the water to boil and serve.