Technique, product and season are the three pillars the restaurant names for itself. What it says it's after is Japanese tradition worked on fish from Spanish waters, pushing sushi towards what it calls its purest expression. One omakase menu, no choosing.

Ebisu started small. Back in Madrid as the pandemic hit, Cortés launched a sushi delivery service, then, as restrictions eased, a six-seat counter in the basement of the wine bar Matritum. In January 2022 he opened a space of his own near Plaza de la Villa, a seven-seat counter whose address was only revealed with the booking. After almost a year spent defining the next step, he moved the restaurant to Calle Luciente in 2023, close to the Mercado de la Cebada, into a plain room with gotelé walls where the only luxury is what's on the plate and in the glass. Everything revolves around a single counter for nine, and diners eat together, facing the itamae for the whole meal.

It keeps a few house rules. There's one menu and no alternative, guests are asked not to wear perfume because it would flatten the subtler bites, and when the booking system shows one seat left, it means exactly one. Flamenco plays through dinner: recordings of Cortés' uncle, the guitarist Gerardo Núñez.

The menu is Edo-style, or edomae: fish cured, aged or marinated before it's served, cut in front of you, with a run of small dishes before the nigiri. Cortés tries to source everything from Japan except the fish, which can't be imported fresh, so the fish comes from Spanish waters instead: red tuna, rock red mullet, melva, scallops. The rice is koshihikari, seasoned without sugar using an aged vinegar brought from Japan, the same one his teacher uses, and he grates fresh wasabi root at the counter rather than using paste.

Eel is one of his specialities. He buys it live from Angulas Roset in the Ebro Delta and cleans it in the restaurant, then serves it as two nigiri, one straight off the grill and one cooked and then marked over the coals. Somewhere among the nigiri comes a tuna and cheese sandwich crowned with caviar, a nod to the school lunch his mother used to make him. The menu is €200 per person before drinks.