Ryuji on Yudofu with "Real Ponzu," and the Cooking of Subtraction That Doesn't Overload on Umami

At the start, Ryuji asks one of the people with him what they eat yudofu with. When the answer is "Ajipon," he says that's not quite it: many people call Ajipon "ponzu," but the original ponzu is this, and he holds up a bottle.

According to Ryuji, real ponzu is made from citrus juice, vinegar and acidulants. Mixing it with soy sauce gives you ponzu shoyu. Ajipon falls into that mixed category, but its taste is "the taste of Ajinomoto," meaning a taste with added umami. He tells them to look at the label on the back, where it says "amino acids," and contrasts this with the real ponzu in his hand, which contains nothing of the kind. The other person responds, "We never had this at home," and hadn't known about this ponzu.

Ryuji says this ponzu has recently become popular as a "pon-sour." He doesn't usually drink much in this series, but says he will this time and gives it a try. The exchange about the brand is hard to make out from the subtitles, but he says something to the effect that cheap shochu is best, and he mixes ponzu into shochu and tops it with a hoppy carbonated drink. Ryuji explains that it becomes a sour that tastes like freshly squeezed citrus. The person who tries it says it's "surprisingly good" and "could work," and there is also a comment that it's sour, so a bit more could have gone in.

Either firm or silken tofu is fine; at the other person's request, they use silken this time. The recipe in the video description is one block of silken tofu (350 g), one Japanese leek (120 g), 250 cc of water and 1 1/3 teaspoons of kombu dashi. Ryuji adds that you can also put in shungiku (garland chrysanthemum), mushrooms, or fish such as cod.

When asked, "Doesn't yudofu usually have kombu in it?", Ryuji talks about the relationship between yudofu and Ajinomoto. According to his explanation, wondering why yudofu, which had long been made with kombu, tasted so good was what led the developer of Ajinomoto to begin researching umami. That's how important kombu is, but kombu is expensive. So this time he uses Hondashi's granulated "kombu dashi." Ryuji says he's been so taken with this seasoning lately that he can't cook without it. Kombu doesn't release much flavor unless it's soaked in water, but since this is granulated, you can just add it as is.

First, put 250 cc of water into a clay pot. You can cut the tofu however you like, but Ryuji just cuts it in half. Some people are afraid of cutting tofu in their hand, but he explains that a blade doesn't cut when you press it, only when you pull it, and demonstrates that pressing the blade against his hand doesn't cut it. You could cut it smaller, but this time he prioritizes appearance and keeps it at this size. If you want to eat sooner, he says, cut it into about four pieces.

Once you add 1 1/3 teaspoons of kombu dashi, honestly, that's it, Ryuji says. Since that would be a bit sparse, he adds a Japanese leek. Cut the leek roughly on the diagonal, discarding any old, dried-out parts. If you don't have leek, you can float something like shungiku instead. Even if it doesn't all fit in the pot at first, it wilts and shrinks as it cooks, so put in the whole leek and cover with the lid. It's fine to start from cold water, and it's ready to eat once it's warm. A little sake adds umami and aroma, but that's only for people who like sake; basically, kombu dashi alone is enough.

Ryuji says leek ranks quite high on the "list of vegetables that change the flavor of a hot pot," and that a pot with leek tastes completely different from one without. He says the smell of leek is as strong as garlic. Partway through cooking, he has the other person smell the pot, and the answer is "leek." Ryuji explains that a change in smell means a change in taste, and that adding leek makes yudofu delicious.

When the other person mentions the sweetness of the leek, Ryuji replies that alliums develop sweetness when heated. He then compares granulated dashi products. Kombu dashi is surprisingly unsweet and a little on the salty side, so it goes well with leek. Hondashi contains sugar and is sweet. Kombu dashi should contain a little too, but it's not as sweet as Hondashi. He then explains that the idea is to transfer the flavor of this broth into the tofu. The simmering time is 10 to 15 minutes, and once the tofu is warmed through, it's ready.

While waiting for it to simmer, Ryuji talks about his approach to cooking. There is food for special occasions (hare) and food for everyday life (ke). Special-occasion food is something lavish like a beef stew simmered for hours, while everyday food is what you normally eat. Ryuji makes both, but says he basically makes food rooted in daily life. Because this yudofu contains nothing but kombu dashi, he says, adjusting the salt is very easy.

From here, Ryuji pushes back against criticism of himself. People who say his seasoning is too strong haven't watched the videos. He's a drinker, so he says in his videos "add a pinch of salt here," and if you leave that out, the flavor will be on the lighter side. He also teaches how to adjust the seasoning. As for the claim that he uses a lot of butter, he concedes that it is a lot sometimes, but says it's just that his recipes with butter are the ones that go viral. To the point that he uses nothing but mentsuyu, he answers that only about 10 of his recipes use mentsuyu. People who say that are going on impressions and don't actually cook, he says. He also says that most people who dabble in chef-style cooking reject him, and that it's fine if they do. He makes easy dishes, and he makes dishes where you sprinkle on Ajinomoto. What matters most, he says, is expanding your repertoire.

After about 10 minutes of simmering, he declares it done. It's very easy, and you can eat rice with it. Since it's tofu, it's cheap, and it's a help on hangover days and the like. Leek is a bit expensive, so half the amount is fine too, he says.

There are two ways to eat it: with salt and with soy sauce. First, serve the tofu as a whole block and top it with the meltingly soft leek. It already has a little kombu dashi flavor, but you sprinkle salt on it and pour on as much real ponzu as you like.

The first person to taste it is surprised: "Wait, it's this good?" They say it's a flavor that brings out the tofu. Ryuji asks, "You can taste the soybeans, right?" and continues, "This is real yudofu." According to Ryuji, this is cheap supermarket tofu costing about 60 yen, and no matter how much you eat, the calories are only those of the tofu. The other person says they had expected it to be more sharply sour, but it's mellow and easy to eat, and it's impressive that salt alone completes it.

When you get tired of salt, next you pour on soy sauce. Ryuji explains that soy sauce contains glutamate umami and recommends adding ponzu and soy sauce a little at a time as you eat. This, he says, is the traditional way to use ponzu. Before Ajipon came out, it was normal to mix this ponzu with soy sauce to make ponzu shoyu, and Ryuji's grandmother did that too.

Ryuji also says that he likes Ajipon, but its flavor is a bit artificial. That's because it's made to make anything taste good. Yudofu simmered in kombu dashi, on the other hand, is best eaten with a sauce that has relatively little umami. When asked whether it's regular soy sauce rather than dashi soy sauce, Ryuji answers that regular soy sauce is fine because the tofu has already absorbed the kombu flavor. It's a low-umami dish by his standards, but precisely because there's less umami, you can really taste the soy sauce. The other person remarks that the soy sauce has a wonderful aroma.

The other person present (called "A-ko" in the chapter list in the description) also tries it, saying you can taste the soybeans and the kombu umami comes through well, and calls it "the taste of a fine Japanese restaurant." Ryuji explains that since it uses no oil at all, it has almost no calories. It's light, so one person can end up eating a whole block, but it's surprisingly filling, so if you're on a diet, you can make do with just this. When the person who tried the soy sauce says they can tell how good the soy sauce is, Ryuji responds, "Doesn't seem like me, does it?" and says it's a dish that also deepens your understanding of food.

When the other person describes it as "the ultimate cooking by subtraction," Ryuji accepts the description. Simmering it with just kombu and salt would be perfectly fine, but kombu is expensive and not something you'd prepare every day, so granulated kombu dashi is fine to use. He stresses, however, that without the kombu dashi it's completely different. He then previews the test in the second half: people who watch his videos will probably want to sprinkle Aji-Shio on this, but actually, this dish doesn't taste good with Aji-Shio.

The leftover broth is full of umami from the leek and kombu. You can add a little water if there isn't enough, but this time he makes zosui with it as is. Here Ryuji introduces a method "nobody knows": taking unheated Sato no Gohan packaged rice and washing it in water as is.

Ryuji explains it like this. When making zosui, you often wash the rice. Since packaged rice ends up being heated in the pot anyway, there's no need to warm it beforehand; you just need to wash off the surface starch. Washing it keeps it from getting slimy, so you get a light, smooth zosui rather than a thick ojiya. Use 200 g of rice, and egg is optional. Add the rice, stir, and once it's warm, add the egg, cover and cook over low heat, and it's ready right away. Ryuji says that being able to handle every unexpected situation is what it means to be good at cooking, and emphasizes that not having to cook rice in advance for the end-of-hot-pot course is useful information.

You can season it with soy sauce, but here again he adds a pinch of salt and a small drizzle of ponzu. The person tasting it responds, "The dashi and ponzu go well together," and "I didn't know they matched this well, zosui and ponzu." Ryuji notes that this isn't a promotion; he's just doing it on his own. The other person comments that this one set makes a dinner, and that with tofu alone you'd want to eat something later, but adding rice makes it satisfying. You could also get by with about 100 g of rice. Ryuji lists the advantages: it's easy, cheap and not fattening, two people can share a small pot, and it's very satisfying for how cheap it is. He also says that for zosui, he might actually prefer it with just salt rather than ponzu.

Ryuji says he wants even people who only make greasy Chinese food to learn this yudofu, recalling that he was like that when he was young. He says you should also make dishes like this with few seasonings. When the other person says they'd like him to do more cooking by subtraction, he answers that he can, he just hasn't been doing it. He's gone with easy-to-understand flavors because he wanted to start out that way, but originally, he says, he was on that side too.

Finally, they compare regular salt and Aji-Shio using the leftover yudofu. After repeatedly stressing that he's not bashing Aji-Shio and that it doesn't taste bad, Ryuji has the other person eat tofu with a little ponzu and Aji-Shio. They notice a difference from the regular salt and say the Aji-Shio version is "too heavy."

Ryuji explains the difference as follows. The ponzu and kombu dashi already contain umami. When you sprinkle on salt that is simply salty, the saltiness and the umami create contrast. If you use Aji-Shio, you end up with "umami-rich tofu plus umami-rich salt," there's no contrast, and the flavor becomes flat. That's why regular salt tastes better in this dish, he says. The other person is surprised that regular salt can taste better than Aji-Shio, saying that at first they briefly thought Aji-Shio would be the one. Ryuji says that it's not as though you should just use Aji-Shio on everything, and that he calculates things to that extent.

When the other person asks whether this is what happens when it becomes "too delicious," a phrase Ryuji often uses, he says yes. Earlier they ate it with just salt and soy sauce, with no umami seasoning in the sauce, and it should still have tasted good, he says. Umami doesn't make food taste better the more you add; add too much and the flavor becomes flat and unappetizing. So Ajinomoto doesn't simply make things taste better when you add it; the amount is what matters, Ryuji says. Cooking is built on careful calculation, and people who reject a dish just because it contains Ajinomoto don't understand the taste of Ajinomoto, he also says. Once you understand the contrast, that too much umami doesn't work either, your cooking range expands enormously. Ryuji encourages viewers to experiment with it themselves, and the video ends.