Seven days of favorite recipes from a chef who loves pasta so much she even makes it on her night off.

Barbara Lynch cooks a lot of pasta at No. 9 Park, her restaurant in Boston. She makes from eight to 10 different pasta dishes a day, ranging from canonical Italian preparations—such as the ribbon-like noodle called trenette with green beans and pesto, a Ligurian favorite—to her own improvisations. (Something she whipped up to feed the staff one afternoon, a flower-shaped pasta with wild mushrooms and mascarpone, went over so well with the dishwashers and prep cooks that her general manager persuaded her to put it on the menu.) Some of her sauces come together in a matter of minutes; others simmer all afternoon. However they are cooked, Lynch's pasta dishes have been one of the chief reasons for No. 9 Park's great popularity ever since it opened over two years ago. A number of customers even request a pasta tasting menu so they can try them all.

This goes on six days a week. On the seventh, the restaurant is closed and Barbara Lynch stays at home. At dinner time, naturally, she makes herself a big bowl of pasta: rigatoni with hot sausage and cannellini beans, a dish so simple and satisfying that she never tires of it.

"It's a fixation," Lynch explains, "maybe even an obsession. I'm fascinated with pasta."

The obsession, if that's the word for it, goes back to her first days in the restaurant business. Almost nothing in her Irish Catholic childhood growing up in public housing in down-at-heels South Boston suggested that she was destined to be a chef whose pasta would make her famous. One summer when Lynch was a teenager, though, she rode the ferry to Martha's Vineyard and hired on to help out in the galley of a dinner-cruise ship. The day before the summer season began, the chef quit. Lynch asked for his job and got it. Then she went ashore to buy every cookbook she could get her hands on. She needed them. She had never worked in a kitchen in her life.

Lynch learned on the job for two summers, then went back to Boston, a seasoned pro. She landed a spot at a restaurant called Michela's, under chef Todd English, and fell in love with Italian food. She learned everything English could teach her, and on her days off, she made her way through the works of Waverley Root and other scholars of Italy's cuisine.

Soon she went to Tuscany to study at the source. A farmer's wife took her in and showed her how to roll gnocchi, how to stew a rabbit, how to make the meat sauce that Lynch now uses in her comforting home-style lasagna.

As she dug deeper into Italian traditions, this Irish girl from South Boston found that her culinary axis was shifting to the opposite side of town. By 1996, when FOOD & WINE named her one of the year's Best New Chefs for her cooking at Galleria Italiana, she was already prowling the cobblestone streets and alleys of the North End several times a week, ducking into Italian groceries, bakeries and salumerias. She still does, loading up on farro, chestnut honey, carnaroli rice and other specialties and hauling them back to No. 9 Park.

Lynch follows her obsession wherever it takes her: to Italy, to the North End or into her own imagination. But as serious as her exploration into the science of pasta is, it's rooted in a simple observation. "I find it very easy to make and fun," she says. And the rewards are so great, considering how minimal the effort. "You can make a really beautiful bowl of pasta, and it may be a totally simple dish, but, my God! it can really make people happy."