“Would you like some extra fat with that?”

That’s not a query most of us are used to hearing. But it’s what you’ll hear from the counter clerk if you purchase some of the duck leg confit at Bierkraft (191 Fifth Ave., Brooklyn, 718-230-7600), the Park Slope gourmet shop. The Biefkraft folks are proud of their confit, and with good reason: Lots of places sell confit, but Bierkraft is one of the few shops that makes its own inhouse. “It’s not hugely popular, but the people who like it tend to buy it regularly,” Bierkraft co-owner Ben Granger, who used to work as the chef at Town, said. “I usually make 5 pounds at a time – about eight or nine legs – and that should last about a week.”

Generally speaking, confit refers to meat cooked in its own fat. It’s particularly popular in southwestern France, both on its own and as a key element in cassoulet. And it’s one of the oldest methods of preserving food – once you’ve made something into confit, it can be covered in the same fat it was cooked in and will keep for weeks, or even months. When you’re ready to eat the stored meat, you put a bit of the fat in a skillet, add the meat, and end up with a nicely crisped exterior.

But all those references to fat can be a turn-off for many people, who mistakenly think confit must be a gloppy, greasy mess. To the uninitiated, the sight of Bierkraft’s confit would probably confirm that misconception: The duck legs sit in a refrigerated display, utterly encased in solid duck fat.

“It’s not for everyone,” Mr. Granger said one recent afternoon. “Some people can’t wrap their brain around it. But where roasting can make something too dry, confit is a braise, so you can’t dry it out. And it’s a braise in fat, which is going to make it super-tender, ultra-soft.”

The most common confit these days involves a duck leg/thigh quarter, which can be made many different ways. “The most important step is the cure,” Mr. Granger said.”It tightens up the proteins and gives you a better product. I do a salt-sugar cure, with a little more sugar than other folks would typically do, because I like it just a bit sweeter.”

After thoroughly coating his duck quarters, Mr. Granger places them on a rack, covers them in plastic, and refrigerates them for 24 to 48 hours, depending on the size of the duck. Then he rinses off the cure, puts the duck in a roasting pan, tosses in a head of garlic and some herbs, adds enough duck fat to cover all the meat, and puts the pan in a very slow oven – about 200 degrees – for several hours.

More fat renders out of the duck as it cooks, so each batch contributes its own character to Mr. Granger’s fat reserve, which he recycles for subsequent rounds. “I’ll taste the fat each time before using it,” he explained. “If it’s too herbaceous, I’ll cut back on the herbs for that batch.”

Some confit recipes are more elaborate than Mr. Granger’s simple herbs-and-garlic approach. At Ivo & Lulu (558 Broome St., 212-226-4399), the tiny French-Caribbean restaurant in SoHo, chef-owner Marc Solomon prepares his duck leg confit with a mango marinade and Jamaican jerk spices, with spectacularly tasty results.

And you can make confit out of more than just duck. “We do goose legs at Christmas,” said Mr. Granger. “And rabbit leg is great, or any kind of sinewy, tougher meat. Basically, anything that you’d braise, it’s that much better if you braise it in fat instead of in wine or stock. And then you can cook potatoes or vegetables in the fat too.”

But rabbit is such a lean animal – how can you cook it in its own fat? “Yeah, you’d have to butcher a hundred rabbits before you had enough fat to make confit,” Mr. Granger said. “So I use duck fat with the rabbit legs. Call it culinary license.”

They take a different sort of license at Urena (37 E. 28th St., 212-213-2328), the new Spanish restaurant in the Gramercy neighborhood, where the rabbit confit appetizer finds magnificently tender pieces of rabbit meat interwoven with shiitake mushrooms.

“We put a weight over the rabbit meat to drive the fat and juices to the surface,” one of Urena’s servers explained. “Then we make the confit with half fat, half oil.” Mr. Granger disdained the weighting approach (“It’s protein, it’s meat – you’d have to put a keg of beer on it to have any effect,” he said), but it’s hard to argue with the results, which are at least the equal of any other rabbit dish in town.

If you want to eat confit at home and don’t live near Bierkraft, no worries: D’Artagnan, the poultry and game specialty brand, makes duck leg confit, which is available at many gourmet shops and some supermarkets. D’Artagnan also sells containers of duck fat, which you can use to make your own confit (see accompanying recipe). And since confit keeps so long, you can make a big batch and eat it whenever you like.

When you’re ready to eat, you can reheat the meat under the broiler or on the grill. But here’s what Mr. Granger recommends: “Get a cast iron pan, put it over a low flame, and put the duck in there, skin side down. Keep it low – you don’t want to burn it. Baste it with the fat you’re cooking it in and then, after maybe 10 minutes, take a look at the skin. Once it’s a nice chestnut brown and crispy, take it out, put it on a paper towel, and season it a little.”

And then? “Serve it with whatever the heck you want,” he said, laughing.”Crispy duck leg, it’s a classic.”

Duck Leg Confit

This recipe comes from Bierkraft co-owner Ben Granger, and is based on the one he uses for the larger batches he prepares at his shop. Mr. Granger recommends rendering your own duck fat and using that to make your confit, but that’s unrealistic for most home cooks, so just buy a few containers of D’Artagnan duck fat, which is available at gourmet shops, some supermarkets, and dartagnan.com.

2 cups sugar
1 1/4 cups kosher salt
4 duck leg/thigh quarters
4 cups of duck fat
4 cloves of garlic
1 sprig of rosemary
1 small bunch of thyme
5 sage leaves
1 bay leaf

1. Mix the salt and sugar in a large bowl. Dredge each piece of duck in the cure mix ture and coat thoroughly, pulling back the skin a bit to ensure maximum coverage. Place the duck on a rack, position the rack over a shallow baking pan to catch any drips, and cover with plastic wrap. Refrigerate for at least 24 hours.

2. Preheat oven to 200 degrees. Remove the duck from the refrigerator and rinse thor oughly to remove all of the cure. Pat dry, place in a roasting pan, and add the duck fat, garlic, and herbs. The pan should be large enough so the duck quarters aren’t overlapping, and the fat, once melted, should completely cover the duck. Cook until velvety soft, or until the skin at the base of the legs begins to pull apart and separate, about 2 to 3 hours. Set aside to cool. Store the duck confit in congealed fat and skillet-fry when needed.