Hand-Cut Steak Tartare from Brad Race, executive chef at Béarnaise on Capital Hill. He serves the dish with mustards and cornichons on the side; diners can use them to customize the raw meat. (Deb Lindsey/For The Washington Post; bowl by Ice Lab Ice Sculptures)

Every once in a while, Kapnos chef-owner George Pagonis will prepare a dish of lamb tartare, carefully plating the beautiful oval of ground meat atop a swish of charred eggplant puree and dollops of harissa, send it to the dining room — and it will promptly come back to the kitchen, untouched.

“A couple of people, when they order it, I guess they don’t know what tartare is. And they’re like, ‘Oh, is this raw?’ And they send it back,” said Pagonis. “You take all this time to make it look nice, and you’re like, what are you doing? I get all upset.”

But occasions for Pagonis to get upset are becoming almost as rare as that rosy-red lamb he’s serving. Diners are rediscovering the pleasures of a plate of velvety raw meat, as steak tartare makes a comeback (along with its Italian cousin, carpaccio).

Raw-meat dishes in ethnic cuisine — the Vietnamese bo tai chanh, Ethiopian kitfo and gored gored, and Lebanese kibbeh nayeh — are, of course, impervious to trends. But tartare, once a mark of sophistication at the “continental” restaurants of old, fell out of favor after the mad cow and E. coli scares of the 1990s. Now that the best restaurants are more cognizant of the conditions in which their animals are raised, diners who were once wary of eating raw meat might be more willing to let their guard down.

“Especially now, with these chef-driven restaurants, chefs are sourcing great products. And these products are more okay [for] eating raw,” said Pagonis. “People are trusting us.”

Ed Witt, the chef at the meaty Partisan, the Penn Quarter restaurant affiliated with Red Apron Butchery, said he’s not surprised to see more diners ordering his restaurant’s beef tartare and carpaccio. Although tuna and other fish tartares superseded raw meat for a time — the Partisan also has a rockfish tartare — for Witt, none of those dishes ever went out of style.

“It’s easy to eat,” said Witt. “You don’t feel bloated, or like you ate a huge piece of meat. You definitely feel like you ate protein, but you don’t feel like, bleghhh.

Food safety experts aren’t the biggest fans of the dishes, though. Any meat that is not cooked to an internal temperature of 155 degrees carries the risk of bacteria or parasites, hence the required government warning, often phrased “Consuming raw or undercooked meats, poultry, seafood, shellfish, or eggs may increase your risk of food-borne illness,” found on many menus.

“Caveat emptor,” said Jeff Nelken, a food safety consultant based outside Los Angeles. “All it takes is a pinhead amount of bacteria to start causing problems.”

The problem with tartare, says Nelken, is that there is no “kill step”: a process, like cooking, that can kill bacteria. He says, though, that better farming practices and in-shell pasteurization of eggs have come a long way.

In December, an outbreak of E.  coli traced to steak tartare at a restaurant in Montreal sickened seven people. But Cliff Coles, president of California Microbiological Consulting, a company that tests food for produce and meat purveyors, said the risk of illness is minimal if chefs prepare well-sourced meat in a clean kitchen using proper technique.

“The beef industry has done a lot to improve not only the quality of the beef but the microbiological quality,” Coles said.

To chefs who flatten slices of beef for carpaccios and concoct the more-elaborate tartares, freshness and origin are paramount.

“Sourcing is the key,” said Witt. “All our stuff, we know where it comes from.” He and all of the chefs interviewed for this story specified which farms were providing their beef.

Chefs differ on which cut makes the best tartare. Witt uses eye round, while executive chef Michael Abt of Le Diplomate uses filet mignon. Pagonis, who uses lamb as a nod to Kapnos’s Greek concept, adds heart because he says it “gives a little bit more of a lamby flavor to the dish.”

“You don’t want anything too fatty,” said Graham Bartlett, the regional executive chef for Richard Sandoval’s restaurants, who uses filet for Toro Toro’s tartare. “The main thing is, you don’t want anything with too much connective tissue.”

For a traditional French tartare — similar to the ones you might have found in Parisian restaurants around the turn of the 20th century, when the dish was called “Beefsteack à l’Américaine” — you might head to Le Diplomate, where Abt mixes diced filet and shallots in a sauce of minced cornichons, chopped capers, Dijon mustard, lemon juice, Tabasco and Heinz ketchup.

“You want it to be mustardy, you want it to be spicy, you want it to be a little briny and salty,” he said. “The ketchup adds a little bit of sweetness to balance it out.”

Steak tartare at Le Diplomate. Chef Michael Abt mixes filet mignon with shallots, cornichons, capers, mustard, lemon juice, Tabasco and ketchup. (Maura Judkis/The Washington Post)

In Le Diplomate’s kitchen, the proportions are critical: Before service, chefs portion out 3.5 ounces of steak in bags and measure out 30 grams of sauce, keeping everything chilled before chopping and mixing it to order.

“You want that nice balance,” said Abt. “If you do 35 grams [of sauce], then it becomes a little too spicy and overpowers. You’ll taste all the sauce, and you won’t really taste the meat.”

At Spike Mendelsohn’s Béarnaise, the tartare is customizable: Guests are presented with mustards and cornichons on the side and can mix the desired amount of fixings into their meat and yolk.

Naturally, every chef puts his or her own personal touches on the dish. At Fiola, the tartare is served with house-made guanciale and a sunny-side-up quail egg. At the Latin-Asian Toro Toro, the tartare is served with a chili pasilla sauce and with rye bread that was soaked in anise and seven-spice-mix-infused milk before being toasted.

“We did it as an experimental thing,” said Bartlett. “It was one of those ones like, should we do it, or should we not? We were sold on it when we made it. The managers eat it for their own meal at the end of the night. It has made the cut.”

Witt’s most important supporting player is the sprouted mustard seeds he folds into his tartare. “You still get the bite and the mustardness from it, but you don’t get the crunch,” he said. “It softens the flavor.” He tops each plate with a salt-cured egg yolk.

At Le Diplomate, where the dish is as traditional as it gets, Abt says tartare has grown in popularity ever since the restaurant opened and has done far better on the menu here than in Stephen Starr’s Philadelphia restaurant Parc, where he used to work.

“I think the D.C. diner is a little more adventurous,” said Abt.

Pagonis said he has found the same to be true. He often includes the lamb tartare on Kapnos’s chef-selected tasting menu, where he has made many converts.

“People kind of get weirded out at first,” he admitted. “We say, try it: If you don’t like it, we’ll take it. They try it, and 98 percent of the time, people love it.”

If they don’t? Well, they might not realize it, but they have just ruined one chef’s night.