Before you start cooking, you have to first soak the seaweed for 30 minutes, allowing it to expand.

In the meantime, you can prepare all the ingredients. Chop the garlic, mushrooms, tofu, and leave all the ingredients displayed in front of you so you can easily add them to the pot.

Add 3 tablespoons of sesame oil to a pot, as well as 4 cloves of garlic, and sauteé them for 1-2 minutes until the garlic is soft and translucent. Bubbles may start to form, but that is a normal reaction of the sesame oil.

Add the ginger powder and stir for a few seconds, involving the garlic and ginger together, and until you can smell the aroma release from the two.

Add the Portobello mushrooms. Stir, mixing them together with the garlic and ginger, and close the pot with lid, leaving it to cook for 10 minutes. As it cooks, the mushroom will release moisture and along with its umami flavor. At the same time, it will also soften and reduce in size, developing the perfect consistency for the soup.

Pour in the 8 cups of hot water and bring it to a boil. Add the seaweed, 2 tablespoons of soy sauce, and 2 teaspoons of salt. Stir and reduce the heat, leaving it to simmer for 10 minutes.

Taste the broth to determine whether it's tasty and has the right amount of soy sauce and salt. Add the tofu, and leave it to simmer for roughly 20 minutes, allowing the flavors to come together.

Turn off the heat and serve the soup onto bowls. Garnish it with spring onions and sesame seeds.