Heat oil in a Dutch oven or large pot over medium heat.
1 tbsp neutral oil
Add the mushrooms, shallot, green onions, and the bok choy. Season with white pepper and soy sauce or tamari. Sauté for about 7 minutes.
7 oz beech mushrooms, 2 baby bok choy, 1 shallot, 5 green onions, ¼ tsp white pepper, 1 tbsp reduced sodium soy sauce or tamari
Add the broth and the firm tofu and cook on low for 15 to 20 minutes.
8 cups vegetable broth, 14 oz firm tofu
Remove the soup from the heat.
Cooked udon noodles or other variety
Add the miso to a small bowl and add a ladle-full of broth to the bowl. Whisk the miso into the broth to create a slurry, then add the slurry to the warm soup and mix it in.
¼ cup yellow miso
Taste the soup for seasoning and serve with optional chili oil.
Spicy chili oil