Cooking by pilot light.

If you want to understand the concept behind Dish, the 12-seat restaurant next to Foody’s in the Water Mill shopping center, it helps to know that chef Peter Robertson is obsessed with “cooking by pilot light.”

He’ll use these small flames that flicker from his six burners, even when they’re off, to melt down some chopped leeks or reduce a sauce or bring already prepared foods to temperature before serving. “It’s part of the reason I like duck,” he says. “I’ll air-dry it all day, and then render the fat on pilot light, real slow. People won’t eat the skin, which is the best part in my opinion. So I render as much of it out as possible.” This is as much about processes— mostly slow and careful ones—as it is about economy. “If I’m going to have the gas on, I might as well cook on it. I can put a big iron pan on these when I’m making bread and then cook slow on that hot pan all day. We try and cut costs everywhere. We turn off the gas, we turn the water and lights off when we leave.”

Everything about this experimental joint depends on stripped-down measures. Stripping away the cacophony of choices, the staff management challenges, the big real estate bills and everything else that challenges running a restaurant. In attempting to satisfy varied palates with one weekly menu, Robertson and his wife and business partner, Merrill Indoe, nightly confront a task less like running a restaurant and more akin to being the main cook in a large household. “People like coming here,” says Robertson. “They don’t have to make any decisions. They just get to chill out.”

Dish has precedents in mom-and-pop operations of yesteryear. Think of it as an upscale, ingredients-driven Nettie’s on Shelter Island, but without the camp or the VCR. More modern analogs, sprouting wherever creative chefs are looking to cook and serve in creative spaces, Beer Table in Park Slope or Joe Doe in the East Village, offer the meticulously edited-down—a rotating tap of three craft beers, paired with a couple of appetizers, mains and dessert choices.

It wasn’t always this way at Dish. When Robertson and Indoe opened last fall—as an off-season complement to their in-season catering company, Corks and Forks—“we ended up throwing away food,” says Robertson. “We would prep and turn everything on, and no one would come. And we felt it was totally crazy.” Indoe—perhaps the accountant and realist of the couple—struck on the current minimalist format. Instead of being Spartan, it was liberating.

“By being reservation-only, we would get exactly what was needed and make it work,” says Robertson. “That’s how we can offer dinner for a low price.” It doesn’t hurt they are the only ones on payroll—except for an occasional server when Indoe isn’t around—or that Robertson’s pilot light mentality squeezes as much flavor and use out of every item that enters his domain. “We’re crazy,” he says. “We want to use everything.”

Here, the line between taste and economy naturally blurs. For instance, Robertson is an avid maker of soups and sauces and stocks. Some corn chowder that he made last fall was showing up in his polenta until early in the New Year. “We just did winter caprese salad with some fresh mozzarella and some canned tomatoes,” he says. After three to four hours of roasting, the concentrated tomato flavor was a preview—if an imperfect one—of summer. He isn’t afraid to feature the same ingredient in multiple courses: Eggs procured from Foster Farm on Sagg Road in Sagaponack end up in homemade pastas, an olive-oil fried egg salad with lentils, and a Tuscan egg salad. Underappreciated cuts of meat also make regular appearances, like the flavorful chain of a beef fillet that was braised into beef bourguignon.

“We can’t really buy prime beef,” says Robertson. “But we don’t need to and for $35 we can’t. We’ll splurge on other things. I’d much rather get fresh fish and shellfish than prime beef.” Indoe listens approvingly. Robertson smiles: “She’s like super cost-conscious. I try to be, but she’s like ‘Dream on’ or whatever.”

Dish blasts out a weekly e-missive about the menu and seat availability to a growing list of would-be diners. Someone craving a dinner with a handful of friends might impetuously reserve a whole table and then rally a group to join. (The two dinners I’ve been to were organized entirely by e-mail, sometimes with the aid of Blackberry’s and later mentioned on Facebook.) “That’s basically how we like to advertise,” says Indoe, “and it seems to just sort of blossom from there.”

The menus feature the comforty (fish and chips), the ethnic (maitake dumplings), the raw (tuna crudo with celery, shallots and toasted bread crumbs), the simple (Blue Point oysters two ways), the old-fashioned (chocolate charlotte russe) and the fusion (shrimp and grits with chorizo and chives). “People come back,” says Robertson, “and they can come every week. Because it’s totally different every time.”

Work begins the day of the dinner, at 11 a.m. or so. He’ll set to making bread, perhaps also the pastry for dessert, and then prepping for dinner. She’ll prepare the tables, the cutlery, and assorted floral arrangements, before leaving to commune with Henry, their golden lab whose portrait adorns both the front and back of the house.

At 4 or 5 p.m., Indoe will return and finish setting up. As the first guests arrive, Indoe sets out some charcuterie or other small tastes and opens whatever bottle of North Fork chenin blanc or Publick House ale the guests have brought. On nights when there is more than one couple or party, the first bites for the earlier guests tempt and tease those who are a course behind. This particular night sees a group of eight golfers and golf widows returning for their second collective visit in as many months. “It’s like making dinner at home but no cooking, grocery shopping or dishes,” one talkative guest quips.

At a certain point, after the men and women have congregated in opposite ends of the small space, an urgency from the kitchen sets the sit-down meal in motion. Surrounded by bowls and colanders of prepared ingredients, Robertson holds a tray of mussels that he had previously steamed, dolloped with a leek-bacon butter (made over pilot light), and topped with panko, that he then browned in the oven for three minutes at 500 degrees. “I do my mise-en-place,” says Robertson. “And then I’ll cook à la minute basically,” he says. “Simplicity goes a long way too. To make this work in such a small space and such a small time window.”

The kitchen, inherited from the welcome but short-lived Indian deli Champa’s, is enhanced with a new Vulcan convection oven, a home fridge and a dough mixer. “I needed him,” says Robertson, pointing at the imposing R2D2-esque device that helps knead flour and water and yeast into the bread set out at every meal. “I can’t not make bread.” He saves money by shaping a half dozen loaves a night, but, like the restaurant, there’s also the appeal of bread’s daily changing character. “I don’t know how my bread recipe was formed. It turned into its own thing. It started as ciabatta, but it’s not French bread either.”

The couple, both 30-year-old Culinary Institute of America grads, met only once while in school together. After graduation, at a wine intensive at Greystone Winery in the Napa Valley, she recognized him (he had initiated their first interaction years before), and within the month they were together.

Indoe grew up in New York and spent time in Southampton as a child. She worked at Loaves and Fishes in Sagaponack as a teenager, and eventually managed the shop. (“I learned a lot there,” she says. “I learned the commitment to buying the best ingredients.”) Robertson’s personal cooking pedigree includes work with Frank Stitt, an adherent of Alice Waters–style farm-to-table cuisine at Highlands Bar and Grill in Robertson’s native Birmingham, Alabama. (Stitt actually gave Robertson his first cooking job at age 15.) When Robertson met Indoe, he was in the middle of a stint as the executive chef at the Stein Eriksen Lodge in Utah’s Deer Valley. Robertson had picked up a fly-fishing habit as an anthropology undergrad at the University of Montana, and fishing near the Stein Lodge was legendary. The resort gave Robertson a generous budget to prepare daily tasting menus—boutique microgreens from Chef’s Garden in Ohio paired with local beef and game—for the 18 guests.

There are glimpses of this dreamy chef scenario at Dish. “It’s nice to be able to do it here on my own terms,” he says, “with Merrill watching my back.”

Starting Memorial Day, after a quick prenuptial roadtrip, Robertson and Indoe will be taking reservations for weeknights, and perhaps weekends. The price may tick up from $35 to $45 per person, still an economical Hamptons choice for a personally designed 5-course dinner.

And Dish may add a liquor license before long, although the guiding principle here is still economy. “We drink a lot of wine and we both know about wine,” says Robertson. But instead of a list, they are leaning toward pairing selected drinkables with their meals. No offense to the wide offerings of wine on Long Island or elsewhere, of course. As with other decisions, the rationale is clear cut, according to Indoe. “We don’t have the space.”

Dish, located at 760 Montauk Highway, Water Mill, 631.726.0246, will be closed from April 19 until Memorial Day weekend. Write to receive their weekly menu and list of available seats.