Miso Soup Recipe

Make dashi from scratch (optional)

If using homemade dashi: Wipe kombu with a damp cloth (do not wash). Combine 4 cups water and kombu in a pot and slowly bring to just under a simmer over medium heat (about 10 minutes). Remove kombu just before the water boils. Add katsuobushi, bring to a gentle boil for 30 seconds, then turn off heat and let sit 2–3 minutes. Strain through a fine sieve or cheesecloth into a clean pot to yield about 4 cups dashi.

If using instant dashi: dissolve instant dashi powder in 4 cups hot water according to package instructions and bring to a gentle simmer in a pot.

Prepare tofu: drain and cut tofu into 1/2-inch (1.2 cm) cubes. Keep refrigerated until ready to add.

Rehydrate wakame: place dried wakame in a small bowl of cold water for 2–3 minutes, then drain and gently squeeze out excess water. Chop larger pieces if needed.

Prepare scallions and mushrooms: thinly slice scallions on the diagonal (both white and green parts). If using mushrooms, trim and slice shiitake or separate enoki stems.

Add fillings to dashi: once dashi is simmering gently (small bubbles, not a rolling boil), reduce heat to low. Add tofu cubes, rehydrated wakame, and mushrooms. Warm gently for 1–2 minutes — do not boil vigorously to avoid breaking tofu.

Temper the miso: scoop 3 tbsp white miso (and 1 tbsp dark miso if using) into a small bowl or ladle. Add about 1/2 cup of the hot dashi and whisk or stir until smooth to make a miso slurry.

Turn the heat to the lowest setting (simmer off). Slowly add the miso slurry back into the pot, stirring gently to combine. Do not boil after adding miso or you'll lose some flavor and beneficial enzymes.

Adjust seasoning: taste the soup and, if needed, add up to 1 tsp soy sauce or a pinch more miso dissolved in a spoonful of broth to reach your preferred saltiness. Keep heat off or very low—just warm.

Serve: ladle soup into bowls and garnish with sliced green onions. Serve immediately.