BARCELONA - If you are strolling these streets and see a curly-haired blonde on a bicycle with a basket of fresh produce, chances are it is Sarah Stothart.

Chef and co-owner of Tapioles 53, Stothart devotes five mornings a week to buying the best of what Barcelona's markets -- Santa Catarina, La Boqueria, and Sant Antoni -- have to offer. On a recent morning, she chatted with her favorite tomato vendors and bought several pounds of heirloom s from the stout, no-nonsense women in housedresses.

"They plant their tomatoes according to the moon," Stothart says later. "Very hippie. They don't look like it, but they are."

Tapioles 53, named after its address, is technically a "food society," rather than a restaurant. Which means a domestic kitchen is used, reservations are required, and one becomes a member simply by eating a meal.

"It has the feel of a speakeasy," says Stothart in her native Australian accent. "There is no name on the door, no advertising, and the majority of clients come through people who have eaten here."

Housed in a renovated umbrella factory in the up-and-coming Poble Sec neighborhood far from the heavily trafficked tourist areas, the cozy 24-seat space serves dinner Tuesday through Saturday. The lighting is low, candles flicker, and bottles of wine line the shelves and cabinets. The small, open kitchen is visible -- and audible, primarily jovial banter between Stothart and her staff of two -- from the surrounding six tables.

Diners are welcomed by the slightly cheeky waiter Roy Gonzalez Perez, the faint sounds of jazz, and the tantalizing aromas of one of the evening's specialties, such as figs stuffed with goat feta cheese and roasted with balsamic vinegar, thyme, salt, and pepper. Emerging from behind the kitchen's counter, Stothart makes her way to each table and explains the menu. She takes great pleasure in going over the details, processes, and oddities such as the arugula that may not look perfect but comes from her parents' garden.

While Tapioles 53's hidden-gem quality and personable service are big attractions, it is the cuisine that keeps drawing Barcelona's dining elite. Whether it is a bowl of mixed olives served with salt crystals Stothart collected in Greece or a salad made with warm garlic dressing, each dish is as thoughtfully and carefully prepared as if the owner was entertaining friends.

"My mum taught me everything," says Stothart, who has never taken a cooking class. "She's an extraordinary cook, never uses recipes, and is one of those cooks that can eat something and know exactly what's in it. She taught that to me."

Tapioles 53's eclectic menu reflects Stothart's upbringing. Before her family settled outside Barcelona some 20 years ago, her parents decided the best education for their children was through travel. Besides Australia, Stothart has lived in Greece, France, Italy, Switzerland, and Spain, and traveled extensively in Malaysia, India, and the Pacific Islands.

In the warmer months, Stothart might prepare dishes such as a starter of delicate, purple basil omelets with a bit of cheddar, layered with salmon, and wild rainbow trout cured in sugar, salt, and dill. For a main course, she offers spinach and fresh goat cheese gnocchi topped with a traditional tomato sauce with bursts of fresh ginger juice, or Thai beef salad with mint served on lettuce-leaf boats. The cheese plate is served with a chilled, homemade Cava jelly and quince paste. As the weather grows colder, Stothart's main courses involve heartier fare such as boeuf Bourguignon or a northern Greek dish of lamb cooked with artichokes, fresh herbs, and lemon.

Tapioles 53 has a set five-course meal -- no substitutions -- for the equivalent of about $68. The more popular option, especially among couples who like to share, is the three-course meal with a choice of two starters, two main courses, and dessert, for about $43.

Stothart wants the focus to be on food, not wine, but she says the vintages she has to offer run the gamut from "strange" to "commonplace," and then back to "weird." She cites the Calvente, for example.

"It's made by these two guys in Grenada out of a garage. But it's really good -- these guys know what they are doing." Wines at Tapioles 53 run the equivalent of $13 to $35 a bottle.

After a leisurely paced meal, dessert chef Noelle Nelson comes to the table and describes her creations. On a recent night, the options were a dark, velvety, flourless chocolate cake with ground almonds and rum, homemade ginger-mascarpone ice cream, and chocolate chip biscuits with homemade coffee ice cream.

Stothart finds her work challenging but gratifying.

"I can look over the bar and see the look on people's faces when they eat my food," she says. That is quite unlike her previous career as an illustrator, where she worked alone and communicated with clients by e-mail. "It's very personal. I feel like the people that have come and eaten here have become friends."

Tapioles 53's success in its two years of existence pleases Stothart, but she still doesn't see it as strictly a money-making venture.

"I don't want to have so many clients that I have to order food instead of being able to go to the markets. And I want people to continue to feel like they are eating in my home," she says.