In a medium pot, bring 6 cups of water to a gentle simmer. If using instant dashi, whisk in 1 tablespoon of dashi granules (or add 1 tablespoon vegetable broth concentrate) until dissolved.

Add aromatics

Add grated ginger (1 tsp) and minced garlic (1 tsp) to the simmering liquid. Simmer gently for 3 minutes to infuse flavor, stirring occasionally.

Incorporate miso

Remove about 1/2 cup of the hot broth into a small bowl. Whisk in 4 tablespoons of white miso paste until smooth, then pour the miso mixture back into the pot. Keep the broth at low heat — do not boil after adding miso, as high heat degrades its flavor and probiotics.

Season

Stir in 1 teaspoon low-sodium soy sauce. Taste the broth and adjust seasoning with a pinch of salt or more soy sauce if needed.

Vegetables & additions

Prep vegetables

While the broth simmers, prepare the vegetables: julienne or thinly slice the carrot (1 cup), slice shiitake mushrooms (1 cup), and slice bok choy into bite-sized pieces (1 cup). Drain and cube 8 oz firm tofu. If using frozen edamame, thaw or briefly blanch and drain.

Cook vegetables

Add the carrots and mushrooms to the simmering miso broth and cook for 3–4 minutes until slightly tender. Add the bok choy and edamame (if using) and simmer 1–2 minutes more until stems are tender-crisp.

Add tofu & greens

Gently add the tofu cubes and 2 cups of baby spinach to the pot. Stir carefully and simmer just until the spinach wilts and the tofu is heated through, about 1 minute. Avoid vigorous stirring to keep tofu intact.

Aromatics & finishing

Finish soup

Remove the pot from heat. Stir in 1 teaspoon sesame oil and 1 teaspoon rice vinegar to brighten flavors. Taste and adjust with salt or a little more soy sauce if necessary.

Serve

Ladle the soup into bowls, garnish each with 1 tablespoon sliced green onions and a sprinkle of toasted sesame seeds (about 1 tsp). If desired, add a pinch (1/2 tsp) crushed red pepper or togarashi for heat and a drizzle of additional sesame oil.