In a pot over medium heat, combine water and half of the coconut milk. Add the galangal, lemongrass, and kaffir lime leaves. Bring to a boil, then reduce the heat and let it simmer to infuse the flavors.

Add the onion, carrot, and mushrooms to the pot. Stir in the vegetarian bouillon, salt, and tamarind paste. Let the soup simmer until the vegetables are tender, then add the tomatoes towards the end to keep them fresh.

Gently stir in the tofu and the remaining coconut milk. Turn off the heat and stir in the dried chilies, cilantro, and green onions. Serve hot and enjoy!