Home-Style Fish Dishes Made with Ingredients from a Fishmonger: Brine-Soaked Horse Mackerel, Saltwater-Thawed Tuna, and Olive-Braised Fish Trimmings

According to Ryuji, he happened to meet Mori at Kuwata's birthday party, and the two hit it off talking about fish. Taisho joined the conversation, the idea of "getting people excited about fish" came up on the spot, and the shoot happened about a month later. Since many people, especially younger ones, have probably never been to a fish shop, the idea was to show what kinds of things are sold there and have Ryuji and Taisho cook with ingredients bought at the shop.

Right inside the entrance, prepared ready-to-eat dishes are lined up. As the Mori side explained, whole fish with the head on don't sell easily, so putting them out already cooked gets people to buy fish. They would really rather sell whole fish, but 80% of sales come from the processed-goods section. Hearing this, Ryuji laughingly admitted that his own channel rarely features head-on fish, so that might be part of the reason.

On the shop floor, they introduced sushi like the crab-and-fruit salad rolls seen at conveyor-belt sushi restaurants, yellowtail trimmings, frozen redfish, and more. Redfish is an ingredient Ryuji used during his restaurant days; it comes as boneless fillets, so it's easy to use, and it's also sold in 1 kg units at places like wholesale supermarkets. It was announced that Ryuji had made a pasta with this redfish on Mori's channel. The yellowtail trimmings were about 400 yen, and Ryuji said, "I'd buy them in a heartbeat."

First up was Mori's salt-grilled horse mackerel. The guts can stay in, but the gills should come out. Mori explained that removing them is better both in terms of bacteria and for peace of mind. This particular fish also had roe inside.

The key is tatejio: soaking the fish in salt water rather than sprinkling salt on it. When you sprinkle salt the usual way, it's hard to distribute it evenly. According to Mori, the general approach is something like soaking the fish in about 3% brine for a day, but at home you can't wait that long. So instead you soak it in a strong 10% brine and finish in about 30 minutes. Ryuji said he hadn't known about this method.

Two signs that the fish is ready were given. One is that the white lens in the eye turns bluish; the other is that touching the skin brings out a slimy film. Soaking in brine draws out excess moisture and fishy odors through osmosis, so it doubles as odor removal. Mori stressed that controlling moisture is extremely important in salt-grilling. Taisho added that at his restaurant, all salt-grilled fish is done this way.

When Ryuji asked, "Wouldn't adding more salt make it even faster?", Mori replied that any stronger and it becomes too salty, so around 10% is the limit. Ryuji was convinced, wondering if it was similar to the principle by which marinating makes things taste better. It works with fillets too, but in that case the salt penetrates even faster.

When the fish comes out of the brine, quite a lot of odor and grime comes out of the belly. Wipe off the moisture thoroughly with paper towels or similar, including inside the belly. Mori explained that grilling the fish dry is what matters.

If you want a restaurant-style finish, apply "decorative salt" to the fins. Rubbing salt on the fins by hand keeps the thin fins from burning and crumbling. Grill over high heat, for about 7 minutes as a guide. But since it varies with the size of the fish, keep an eye on the browning as you grill. For a whole fish, it takes more than 5 minutes, so check on it at 5 minutes first. Ryuji remarked that the reason so many people avoid using their fish grill is probably because this kind of judgment is hard at home.

Next, Mori's father taught how to thaw a frozen block of yellowfin tuna. If you let it thaw naturally, the outside and center thaw at different rates, and the core turns dark. To thaw it all at once, the father recommends thawing in warm water, a method he called "unorthodox, and maybe scary for everyone."

Add about 10 g of salt to 800 cc of warm water at around 40°C, just a bit warmer than skin temperature. Ryuji described it as "about like a slightly strong soup." Put the frozen block in as is. When the surface gets a little slick and the color brightens, pull it out and then just keep it in the fridge.

According to the father, thawing in the fridge takes days, during which the color deteriorates and drip comes out, taking flavor with it. With this method, he said, no drip comes out. It also avoids the dryness typical of frozen tuna and gives a chewy, springy texture, and it was presented as a way to make cheap tuna taste good. In fact, within a few minutes it was soft enough to slice, and Ryuji, tasting it, said it was "springy." The father wrapped up with a joke: "Don't get in the bath with your tuna."

Ryuji made a tartare with the thawed tuna. Slice about 120 g of tuna with a pulling cut. Peel the avocado like a banana; since it was large, use half. According to Ryuji, avocado has its own fat and is a strong-flavored ingredient, so it's delicious with skipjack or white fish instead of tuna.

Chop about 5 shiso leaves, combine with the tuna and avocado, and add 2 pinches of salt and 1.5 tablespoons of olive oil. Mayonnaise works instead of olive oil. Adding the oil helps the avocado coat everything. Then add lemon juice. Vinegar is fine too; it's better to have some acidity.

He added two packets' worth of wasabi. Ryuji explained that wasabi loses its heat once oil is added, so two packets is fine. They also mentioned that pickled ginger or black pepper would probably go well mixed in. Avocado darkens over time without acid, but since lemon is added, it won't turn dark and still looks good if made ahead. Ryuji said it's a stylish dish that also goes well on a baguette, and it takes little effort. He finished by scattering chopped shiso over it like parsley and drizzling with olive oil.

Next was olive-braised yellowtail trimmings, a dish Ryuji says he actually makes at home. According to Ryuji, it's close to acqua pazza, a version without hard-to-find clams.

For 700–800 g of yellowtail trimmings, use 30–40 g of large domestic garlic. Apparently you can add as much garlic as you like. First, pour in plenty of olive oil, sear the yellowtail, and season boldly with salt. You can cut up the larger pieces, but since the fish shop has already cut them, leaving them as is is fine. Ryuji said the great thing about trimmings is that because the shop has cut them for you, you don't have to do anything difficult.

Add the garlic while the fish cooks. The fish's moisture cooks off and the garlic becomes fragrant, so once everything is seared, the fishy smell is gone. Then add pitted olives. Ryuji says he uses olives often himself and noted this is probably not something many people do.

Add 500 cc of water. Asked whether it would burn, Ryuji answered, "Even if it scorches, the water dissolves that flavor, so it's no problem." The heat can stay on high right to the end. Ryuji explained that acqua pazza means "crazy water" and is a dish you bring to a rolling boil, adding "there are various theories." He laughed that if he didn't say that, people would make a fuss.

The only seasoning is salt, about half a teaspoon added at the end. Ryuji would normally use umami seasoning, but says it isn't needed because flavor comes out from around the bones. If you want to add vegetables, turnip or daikon works well, turning it into a Western-style yellowtail-and-daikon. Ryuji explained that when a dish requires prep, people say "I'm never making that again," so he suggests dishes that need no prep.

From here on, the dishes were Taisho's. He picked very fresh sardines from Kochi Prefecture and taught an easy vinegar cure that can be done at home.

First, open them by hand. Remove the head and open the fish with your fingers; if the fish is fresh, the backbone comes away from the flesh cleanly. Opening with a knife gives a neat result, but the belly bones remain, and dealing with them takes extra work. So at home, opening by hand is actually better, Taisho explained. The prep was done in about 3 minutes.

Salt the opened fillets fairly generously and let them sit for about 5 minutes. Then rinse off the salt. However, when the fish are fattier, he handles them differently, judging by looking at the fish.

The curing vinegar is 8 parts vinegar to 2 parts light soy sauce. Add a little under 1 teaspoon of sugar. If you have kombu, add it too, in which case you can cut the sugar by about half. When Ryuji checked, "So the sweetness stands in for umami?", Taisho said yes. Ryuji said he had learned vinegar curing long ago but had never heard of adding light soy sauce. According to Taisho, the light soy sauce is for saltiness and a little umami.

Submerge the fillets just enough to cover them, for about 2 minutes. This is to avoid over-curing, and within less than a minute the flesh had turned white. Wipe off the moisture and remove any remaining belly bones. With sardines this size, you can eat them without peeling off the skin. Taisho said the ends trimmed off to tidy the shape are a waste to throw away at home, so you can just plate them too. The whole dish takes about 15 minutes.

Next was in-season firefly squid. Taisho announced he would make it into namero, combine it with sushi rice, and put a twist on it.

For prep, the eyes and beak are best removed, but the cartilage can stay since it all gets chopped anyway. Something like tweezers makes it faster. Ryuji said he had been taking them apart completely until now.

Coarsely chop the firefly squid, add shiso, grated ginger, and leek, and season with about 2/3 teaspoon of soy sauce and about 1.5 teaspoons of mayonnaise. Ryuji was surprised by the mayonnaise. No miso is used; the squid's own innards play the role of miso. According to Taisho, this time the squid was from Hyogo, so he added mayonnaise. Depending on where they're from, the innards can be richer, in which case mayonnaise isn't needed.

Normally this would go on top as gunkan sushi, but this time he made an "unconventional" version mixed into the sushi rice. He shaped it flat on aluminum foil and grilled it like a yaki onigiri. At home you can shape it into rounds and grill it in a toaster oven at the highest setting until the surface is crispy. Taisho has been making this dish for about 20 years, and at his restaurant he serves it with a little more chopped namero on top of the grilled rice.

Tasting the salt-grilled horse mackerel, Ryuji praised how plump the flesh was. He said he had only ever made grilled fish by sprinkling salt, and he could feel the difference. "Mizu-chan," who is said to be a tough grader, also tried it and said it was delicious.

With the tuna and avocado tartare, there had been worries since the tuna was frozen, but the reaction was that it didn't taste frozen at all. Letting it sit a while seemed to have brought the flavors together. Ryuji explained that it's rich and creamy even without mayonnaise because the avocado melts and coats everything like a dressing. That's why, in Ryuji's view, you don't need expensive tuna.

There was also a note on storage. Avocado doesn't do well with metal, so storing it in a metal bowl makes the color deteriorate. It's better to put it on a ceramic plate and cover it with plastic wrap. Ryuji added that basil and the like also discolor quickly.

Tasting the olive-braised yellowtail trimmings, Taisho said even the dark meat was delicious. In Japanese cuisine you're told to cleanly remove parts like the dark meat, but in this dish simmered with only salt, the parts called trimmings actually become a source of flavor. Ryuji said you could also make it by adding other trimmings, such as sea bream or salmon. To finish, if the pasta says to boil for 10 minutes, boil it for about 7 and then simmer it the rest of the way in the broth so it soaks up the flavor.

Here the conversation turned to the "taboos" of fish cooking. Ryuji pointed out that fish cooking has too many "you mustn't do this" rules, which raises the barrier to entry, and said he wants to break them down. Taisho said he sympathizes with Ryuji's stance.

According to Ryuji, whenever he posts a fish-cooking video, he gets a flood of "that's wrong" comments. Mori also often gets criticism on their own YouTube channel, such as being told not to break down fish from the belly side. Ryuji responded, "Just let them talk," while acknowledging that breaking down fish cleanly is of course important. Even so, his position was that trying to follow every rule makes fish far too intimidating.

The vinegar-cured sardines were well received for their authentic flavor. Taisho said the most important point is adding sugar to make a sweet vinegar. When Ryuji said he disliked vinegar-cured fish as a child, Taisho replied that what he'd had might have been pickled in vinegar rather than vinegar-cured. Since this cure isn't harsh, he hopes to feed it to small children so they come to love fish.

Of the namero fried rice, Ryuji said you can enjoy it in three stages: the aroma of the miso, the aroma of the shiso, and the aroma of the vinegar. Someone said they'd like to eat it as a big rice ball, and the conversation turned to whether the fish shop's prepared-foods section could sell it as yaki onigiri. The Mori side responded that sardines and firefly squid would probably sell well starting tomorrow, so the episode would be a plus for the fish shop too.

Finally, Taisho took on a challenge requested by the Mori side. A customer had wanted only the kamatoro (collar fatty tuna) from the small tuna the shop had bought that day and didn't want the rest, so could something be done with it?

Taisho scraped the meat off with a spoon. Quite a lot of meat that a knife can't fully remove comes out. It's not that you can't eat it as is, but it has sinew, so he cooked it. Once cooked, the sinew is no longer noticeable. Taisho called the white fatty part "tuna lard" and said that if you cook with it, you might not need oil. Ryuji responded that making ramen with it might be interesting too.

He mixed the scraped meat with salt and pepper, chopped green onion, and grated ginger, cooked it like a hamburger patty, and in the open space of the same frying pan made a sauce by combining sake, soy sauce, and mirin. He added wasabi as well. The dish is properly called kuwayaki, but this time he made it in a single frying pan.

Tasting it, Ryuji said it was fluffy inside, quite meaty, and the kind of flavor that makes you want rice. Someone suggested it would be good with an egg on top, and the episode ended with jokes about collecting leftover collars at the shop to make this and serving it as a lunch special tomorrow only. Taisho's dish, which used up the parts that go unsold, was the last of the episode.