Beyond the escalope San Román, there's the tarta de queso, the cheesecake that helped make the place famous, built for cheese lovers from three cheeses: fresh, smoked Idiazábal and blue.

Dishes from the early menus that set the tone include squid with endives, veal sweetbreads with beetroot, a chilled green-tomato cream, tuna belly with pickled strawberries, house-made pâté and house-infused spirits.

Redruello first wanted to open a restaurant specialising in breaded and fried dishes, and the name comes from that idea: it nods to Figlmüller, the Viennese house famous for its schnitzel. The concept then turned north, to the spare, product-first style of Scandinavian dining, but the name stayed. When it opened on Calle Sagasta in 2016, the room was designed by Arquitectura Invisible, the studio of Nino's brother Ignacio Redruello, with the interior designer Alejandra Pombo: bare plaster walls, steel, concrete floors, reclaimed-wood tables, carbon-filament bulbs and wicker lamps, with a metal service bar in each room and some communal tables. From the start, every wine on the list has been available by the glass. There is also a Fismuler in Barcelona.

Fismuler belongs to Familia La Ancha, one of Madrid's longest-running restaurant families. After La Estrecha, the second generation, Santiago Redruello, renamed it La Ancha; it moved to Calle Velázquez in 1957 and to Príncipe de Vergara in 1969, and a second La Ancha opened on Zorrilla in 1988. Since the fourth generation took over in 2005, the group has added Las Tortillas de Gabino, Fismuler, Armando, Taberna de la Ancha, The Omar, Hijos de Tomás, Molino de Pez and the restaurant of the Club Financiero Génova.

Fismuler opened on Calle Sagasta in 2016, founded by Nino Redruello, Patxi Zumárraga and Jaime Santianes, three cooks who came out of elBulli. It belongs to the La Ancha group and has since opened sister Fismulers in Barcelona, Lisbon and Andorra. Zumárraga left at the end of 2022 and now runs Haramboure. Fismuler is recommended in the Michelin Guide and holds one Repsol Sol.

The cooking is seasonal, ingredient-led and made for the table to share. Two dishes have become Madrid signatures: the escalope San Román, a breaded pork schnitzel named after a regular, served with egg and truffle, and the cheesecake built for cheese lovers from fresh cheese, smoked Idiazábal and blue.

Around them, the carta has run to little gem lettuce from the house garden, a pork-ear sandwich with brava sauce, a courgette-flower fritter, burrata with green mole, hamachi aguachile, green-bean stew with torreznos, a grilled sardine omelette, baby-squid carbonara, creamy red rice with fried crab, Cantonese-style fried red snapper, meatballs in peanut sauce, steak tartare and suckling-lamb shoulder.

The room is casual and industrial, candlelit and full of character, and often has live music.

The dining room is open Monday to Thursday from 13:30 to 01:00 and Friday and Saturday from 13:30 to 02:00. The kitchen serves lunch from 13:30 to 15:30 (16:00 on Friday and Saturday) and dinner from 20:00 to 23:00 (23:30 on Friday and Saturday). Book through the reservation link on its site or call 91 827 75 81.