Sumashi-jiru, Clear Dashi Soup with Tofu
Sumashi-jiru is the clear soup of a Japanese meal, the quiet counterpart to miso soup, and it lives or dies on the dashi. With nothing to hide behind, the broth has to carry itself, so the whole effort goes into drawing a clean, deeply savory stock from kombu and dried shiitake and then barely seasoning it. A few drops of tamari are all it takes; the aim is to taste the dashi, not the salt. Soft cubes of tofu and a raw leaf of watercress dropped into the bowl are the entire garnish. It is a lesson in restraint, and the reason Japanese cooks treat a good dashi as the foundation of everything.
Ingredients
- 1 piece Kombu, 4-inch (10 cm) square
- 3 pieces Dried shiitake
- 7 oz Silken tofu, about 200 g, cut into small cubes
- 2 tsp Low-sodium tamari
- 2 pieces Scallions, thinly sliced on the bias
- 1 handful Watercress, small, tender sprigs
Method
- Steep the kombu and dried shiitake in 4 cups (950 ml) cold water for at least 20 minutes, or hours if you have them, then heat slowly and lift the kombu out just before the water boils. A slow, cold extraction pulls clean glutamate from the kombu and guanylate from the shiitake, the two savory compounds that make dashi taste of far more than water; boiling the kombu turns the broth cloudy and bitter.
- Simmer the shiitake alone for another 5 minutes, then lift them out and slice thin. The mushrooms give the dashi its backbone, and sliced back in they become the soup's only real substance beside the tofu.
- Season the clear broth with just the tamari, adding it a little at a time. A suimono is defined by restraint, so you want to taste the dashi first and the salt second; stop while the broth still tastes gentle.
- Warm the tofu cubes and sliced shiitake in the broth for 2 minutes without letting it boil. Silken tofu needs only to heat through, and a hard boil would break the cubes and roughen the clarity of the soup.
- Set the scallion and watercress in the bottom of each bowl and ladle the hot broth over them. Adding the greens raw and letting the broth wilt them just enough keeps their color and scent fresh, which is the aromatic finish of a clear soup.
Nutrition
Estimated per serving: 45 calories, 4 g protein, 1 g fiber, 240 mg sodium. Computed from USDA FoodData Central reference values for the main ingredients. This is an approximation, not a laboratory measurement. How these are computed.
Cost per serving is estimated from US national-average retail prices for cheap staple forms, using BLS dried-bean prices and USDA produce prices. Prices vary by store and season, so treat it as a guide, not a receipt. How this is computed.
