Beyond the peppers and asparagus, the kitchen runs alubias pochas de Sangüesa, an aged-beef chuletón off the grill, and a caramelized torrija for dessert. It's a regulars' place, the kind people come back to because they know they'll eat well.

Chef Juan Miguel Sola and his wife Anabel Arriezu opened La Manduca de Azagra on Calle Sagasta in 2003, bringing their Navarran roots to Madrid. It is named after Azagra, the Navarre town whose produce anchors the menu, and it has become a regulars' place, the kind people come back to because they know they'll eat well. It holds one Repsol Sol and won the Academia Madrileña de Gastronomía's Regional Cuisine Award in 2023.

The vegetables come from the family's own market gardens in Azagra, in the Ribera of Navarre, where his aunt Mari and his cousins grow them; the artichokes carry Aunt Mari's name on the carta and the cardoon Uncle Lázaro's. Each morning, soon after dawn, a van unloads the day's produce on Calle Sagasta after a drive of close to four hours. Sola's line is that every day he brings Azagra to Madrid.

The famous crystal peppers are roasted over vine-shoot embers, and the kitchen serves them on their own or with two fried eggs. The rest of the carta follows the seasons in the garden: artichokes, leeks, green garlic, peas, cardoon, borage, broad beans and white asparagus, or a menestra of whatever is best. Sharing, or asking for combined half portions, is the way to try several.

Sola commissioned the room from the Navarrese architect Patxi (Francisco) Mangado, a friend from his days selling architectural products; architecture photographer Roland Halbe shot it for the restaurant's site. At first some critics and diners found the design cold, but the space is generous and the tables are set far enough apart that you don't hear the next table's conversation, which suits a discreet lunch. It serves up to about a hundred guests a day between lunch and dinner.

The guest list over the years has run from politicians and athletes to artists. Lou Reed ate there with Laurie Anderson hours before a Madrid concert in July 2009, was served the house piparras with a warning that they might be hot, and told the crowd that night that if his voice gave out, the piparras of La Manduca de Azagra were to blame.

The vegetables are the heart of the carta: roasted crystal peppers (dedicated on the menu to 'Pili') and fried eggs with crystal peppers, white asparagus, leeks, chicory, a vegetable medley, borage with broken egg and ham, Aunt Mari's artichokes and Uncle Lázaro's cardoon. Spoon dishes include pochas beans from Sangüesa and a lentil stew with vegetables.

From the sea come battered fresh anchovies, hake baked or battered, wild sea bass, grilled hake collar, monkfish, red porgy and sea bream; from the land, veal cheeks, boneless oxtail with boletus, baby-lamb chilindrón, battered lamb brains, confit suckling pig, grilled sirloin and an aged-beef T-bone from the grill. Starters run to ensaladilla rusa, ham croquettes, Santoña anchovies and foie gras terrine, and desserts to a caramelised torrija, pantxineta, rice pudding and Ulzama-style burnt curd.

When it appears, the potato tortilla is made with three eggs per diner and folded like a French omelette, in the style of the one at the Kasino in Lesaka. The wine list is short, moderately priced and leans on Navarre.

La Manduca de Azagra serves lunch and dinner Monday to Friday (13:30 to 18:00 and 21:00 to 00:45, with the kitchen open 13:30 to 15:30 and 21:00 to 22:30) and lunch only on Saturday (13:30 to 17:30). It is closed on Saturday evening, Sunday, public holidays and throughout August. Call +34 915 910 112 to book. The room is cosy and family-friendly.