Wild mountain vegetables in tofu dressing

Unpacking the history of shira-ae, a white tofu dressing, the terms "shirazu" (white vinegar dressing) and "shira-ae" both appear in the Edo-period Ryori Monogatari (Tales of Cooking, published 1643). It states, "Put tofu into mustard, adjust with salt, and thin it out with vinegar. For shira-ae, don't add vinegar -- grind it in well instead," which shows that, unlike today, tofu wasn't the main ingredient. Mustard was the main ingredient, tofu went into it, and salt adjusted the seasoning. The version with vinegar added was "shirazu," and the version without it was "shira-ae." However, according to the Ryori Chinmi-shu (Collection of Culinary Delicacies, published 1764), which gathered up newly created delicacies from the same Edo-period Ryori Sankaikyo, a dish where the white part of scallion was parboiled and dressed with tofu mixed with sesame miso is recorded as "Fuji-ae," and a dish where fish was cut into small dice, boiled, and dressed with miso, tofu, and sesame is recorded as "shira-ae" -- so by then, the main ingredient had already become tofu, just as it is today. And in the "shirazu" that appears in the Meiji-era Nihon Ryoriho Taizen (Complete Guide to Japanese Cooking Methods, published 1898), tofu is again the main ingredient, as shown by the description "drain the water from tofu, add white sesame, grind, mix into vinegar, and strain." Since shojin (Buddhist vegetarian) cuisine originally had dishes that used tofu, it seems to me that shira-ae, with its coat of white dressing, is also a dish heavily influenced by shojin cuisine.

For shira-ae, draining the water out of the tofu is what matters most. Draining it raw, without boiling, tastes better, but during seasons when things spoil quickly, it's better to boil it first and then drain the water. When you wring it out in a cloth, some tofu will seep out through the weave, so be careful not to wring it so hard that you squeeze out the soy milk along with it. Wringing it too dry leaves it crumbly and dry, and not wringing it enough is no good either, so getting the balance right is the key point.

Also, season the ingredients you'll be dressing with a base seasoning ahead of time. Here, we've seasoned the wild mountain vegetables (sansai) with a lightly flavored dashi.

1. Set the tofu on a cutting board propped at an angle, and leave it as is for 30 minutes to an hour to drain the water.

2. Next, wring out the water further by twisting it in a dry cloth. If you're boiling it during the summer months, the key points are the heat level and how it floats. Don't let it come to a full boil, and lift the tofu out once it starts to float.

3. Strain the drained tofu through a sieve to make a fine, smooth paste.

4. In a suribachi mortar, add sugar, salt, and sesame paste and mix together, then toss with butterbur (fuki) and bracken fern (warabi) and plate it.