Steamed Komatsuna and Tofu
Quick answer
Komatsuna mushi is a Japanese steamed dish of mustard spinach and tofu, finished with a poured dashi-soy sauce.
What makes this special
- Komatsuna-mushi maintains a firm vegetable bite against soft tofu in a light dashi-soy broth.
- Komatsuna's firmer stem and milder bitterness than spinach survive steaming with texture intact
- Dashi and soy-only sauce uses zero oil to let the ingredients speak for themselves
Key ingredients
Core cooking flow
- 1 Rinse 180 g komatsuna, shake off excess water, and cut it into 5 cm lengths.
- 2 Cut 300 g soft tofu into roughly 2 cm cubes and set them briefly on paper towels.
- 3 Arrange the komatsuna stems on the steaming plate first, then the tofu, then the leaves.
Komatsuna mushi is a Japanese steamed dish of mustard spinach and tofu, finished with a poured dashi-soy sauce. Komatsuna has less bitterness than regular spinach and keeps a firm bite after steaming, which stands in textural contrast to the soft tofu beneath it. The sauce is made from kombu and katsuobushi dashi seasoned with soy sauce and salt alone, so there is nothing artificial in the flavor and each ingredient comes through cleanly. No oil is used anywhere in the preparation, making this one of the lighter dishes in a multi-course Japanese home meal, where it commonly appears alongside several other small plates. A small amount of bonito flakes laid over the tofu at the end adds fragrance and gives the dish a tidy, composed appearance.
Instructions
Read the steps as a cooking flow: prep, heat, seasoning, doneness control, and finish.
- 1Prep
Rinse 180 g komatsuna, shake off excess water, and cut it into 5 cm lengths.
Keep the stems and leaves slightly separated so the firmer stems can be placed where they receive more heat.
- 2Season
Cut 300 g soft tofu into roughly 2 cm cubes and set them briefly on paper towels.
Draining the surface moisture keeps the dashi soy sauce from tasting diluted after steaming.
- 3Finish
Arrange the komatsuna stems on the steaming plate first, then the tofu, then the leaves.
Leave small gaps instead of piling everything tightly so steam circulates and the tofu keeps its shape.
- 4Finish
Once the steamer is boiling, add the plate and steam over medium heat for 7 to 8 minutes.
Stop when the leaves look bright and wilted and the stems bend slightly but still hold some bite.
- 5Control
In a small pan, warm 80 ml dashi with 1.5 tablespoons soy sauce over low heat.
Do not boil it hard; turn off the heat as soon as steam rises and the aroma opens.
- 6Finish
Pour off a little excess liquid from the steaming plate, then spoon the warm sauce evenly over the tofu and greens.
Finish with 1 teaspoon sesame oil and 1 teaspoon sesame seeds, and serve while warm.
After the steps
Pick a recipe that fits this dish.
Continue with shared ingredients, meal pairings, or a similar method.
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