Most confit recipes ask for enough duck fat to submerge six legs, which is somewhere between a kilo and a kilo and a half. At the price duck fat sells for, that is the single most expensive ingredient on the list, and it is the reason most people read the recipe and then cook something else.
Six legs cooked in a narrow ceramic dish, packed upright and tight, needed 380 grams of fat to start with. By the second hour they were fully covered, because the legs themselves had rendered close to another 300 grams into the dish.
Fat is not the cooking medium in the way frying uses oil. It is an oxygen barrier and a heat conductor, and both of those jobs are about coverage rather than volume. Here is how little you actually need, what six hours at 190F does that three hours at 300F cannot, and an honest account of how long a sealed jar keeps.
- Fat to start: 350 to 400 g for six legs in a narrow dish, not 1.2 kg
- Rendered during the cook: roughly 50 g per leg
- Cure: 1.2 percent salt by weight, 12 to 24 hours
- Cook: 190 to 200F for 6 to 8 hours, covered
- Done when: a skewer meets no resistance and the bone wobbles
- Keeps: a few weeks refrigerated under fat, months frozen
- Crisping is separate: hot pan or hot oven, skin down, at serving time
Six legs and a third of the fat
The instruction to submerge comes from a technique that predates refrigeration, where the fat cap was the preservation and the depth of it was insurance. In a kitchen with a refrigerator, the depth is doing much less than it used to.
What still matters is contact. Every part of the meat needs to be under fat during the cook, because anything exposed to air dries and browns instead of confiting. That is a geometry problem, not a volume problem, and geometry is solved by choosing a smaller dish.
Six legs laid flat in a roasting pan need to be drowned. The same six packed standing in a deep, narrow casserole need a third as much, and by hour two they have rendered enough of their own to cover themselves anyway.
What the fat is actually doing
Three things, and none of them is frying. At 190F the fat is nowhere near frying temperature and no browning occurs at all, which is why confit comes out of the pot pale and has to be crisped separately.
First, it conducts heat evenly around every surface of the leg, so the whole thing sits at the same temperature for the whole cook. Second, it excludes air, which stops the exposed meat from drying and oxidizing over six hours. Third, when it cools and sets, it forms a seal that slows spoilage in storage.
The fat also does not penetrate the meat to any real degree. A confit leg is not greasy inside; it has actually lost fat rather than gained it, since its own subcutaneous fat renders out into the pot. That is worth knowing because it is the opposite of what the technique looks like.
How little fat you need, measured
| Vessel for 6 legs | Fat to start | Rendered by hour 2 | Coverage |
|---|---|---|---|
| Wide roasting pan, flat | 1200 g | 300 g | full, wasteful |
| Dutch oven, two layers | 700 g | 300 g | full |
| Deep narrow casserole, upright | 380 g | 300 g | full by hour 2 |
| Loaf pan, tightly packed | 300 g | 300 g | full by hour 2 |
| Sealed bag or jar, water bath | 2 tablespoons | 300 g | full, contact only |
The bottom row is the extreme case and it works. In a sealed bag there is no air to exclude, so a couple of spoonfuls of fat for lubrication is genuinely enough, and the legs cook in the fat they render. It is not traditional and the result is very close.
The practical middle is the narrow casserole. Pack the legs standing on their thick ends, bone up, with as little space between them as they will allow, and start with enough fat to come two thirds of the way up. It will be over the top of them within two hours.
The cure, and why it comes first
Salt does three things before any heat is involved. It seasons the meat through rather than on the surface, it draws out some water and firms the texture, and it lowers the water available for bacterial growth, which is the preservation half of the technique.
Weigh the legs and use 1.2 percent of that weight in salt. Six duck legs run about 1.4 kilograms, which is 17 grams. That is far less than the classic instruction to bury the legs in a bed of salt, and it is far more controllable, since burying gives you a result that depends on how long you happened to leave them.
Twelve to twenty-four hours in the refrigerator is the window. Add crushed garlic, thyme, bay and coarse black pepper if you like, rub the mixture over every surface, and turn the legs once. Then rinse briefly, and dry them thoroughly, because water left on the skin will spit when it meets hot fat and will dilute the seal in storage.
The duck confit method, cure to jar
- Weigh the legs and calculate 1.2 percent salt. Write the number down. Six legs, about 17 grams.
- Rub the salt and aromatics over every surface and refrigerate 12 to 24 hours. In a covered dish, turned once.
- Rinse the legs and dry them completely. Pat, then leave them on a rack for an hour if there is time.
- Pack them upright and tight in the narrowest vessel that holds them. Bone end up, skin outward. Crowding is the goal here.
- Add fat to two thirds of their height and warm it gently on the stove. Just until it is liquid and the legs are surrounded. It should not sizzle.
- Cover and put it in a 190F oven for six hours. Check after twenty minutes that nothing is bubbling. A bubble means the oven is too hot.
- Test at six hours with a skewer through the thickest part. No resistance, and the bone should move independently of the meat when you twist it.
- Let the whole thing cool to room temperature in the fat, without moving the legs. They are fragile hot and they firm up as they cool.
- Transfer to jars or a crock and strain the fat over them. Let the cloudy meat juices settle to the bottom of the pan first and leave them behind, since juice under the cap shortens the keeping time considerably.
- Make sure the fat covers everything by at least a centimeter, then refrigerate. Any leg poking through the cap is the one that goes off first.
What six hours at 190F does
Duck legs are working muscle, dense with connective tissue, and the collagen in that tissue converts to gelatin slowly. The conversion runs from about 160F upward and the rate climbs steeply with temperature, so there is a real choice between a long gentle cook and a shorter hotter one.
At 190F the conversion is unhurried and the muscle fibers themselves never get hot enough to contract hard and expel their water. What you get after six hours is meat that has gone completely slack, holds together until you push it, and is still moist inside.
At 250F the same legs are tender in about three hours, and they are noticeably drier and stringier. The collagen converted, but the fibers also squeezed, and the difference between the two is the entire argument for spending the afternoon on it.
Temperature, compared across the same six legs
| Oven | Time to tender | Texture | Fat rendered |
|---|---|---|---|
| 175F | 9 to 10 hours | silky, very moist, fragile | least |
| 190F | 6 to 7 hours | slack, moist, holds together | moderate |
| 215F | 4 to 5 hours | tender, slightly firmer | more |
| 250F | 3 hours | tender but stringy, drier | most |
| 300F | 2 hours | the fat bubbles, this is frying | most, skin damaged |
The bottom row is the line where the technique stops being confit. Once the fat is bubbling, water is boiling out of the meat and the process is a slow fry, which produces something perfectly edible and not what the method was for.
Home ovens are frequently off by twenty-five degrees at these settings, and at 190F a twenty-five degree error is a large proportion. An oven thermometer sitting on the shelf next to the dish is worth more here than in almost any other application.
Keeping it under its own cap
The traditional claim is that confit keeps for months in a cool larder under a sealed layer of fat, and historically that is exactly what people did. The larder in that claim was doing a great deal of work: a stone room at cellar temperature, a heavily salted bird, and a household eating from the crock regularly.
In a modern kitchen the sensible version is a few weeks in the refrigerator, fully submerged, in a clean sealed container, with none of the meat juices carried over from the cooking pan. The flavor genuinely improves over the first week or two as the salt and aromatics settle through the meat.
For longer than that, freeze it. Confit freezes exceptionally well in its fat for six months with no loss of texture, and thaws in the refrigerator overnight. That removes the whole question, and it costs nothing but freezer space.
Where the old claims meet modern food safety
A layer of set fat over cooked meat is an oxygen-free environment, and low-acid food held without oxygen is precisely the condition under which the botulism organism can grow if the temperature allows it. The salt cure and the refrigerator are what make that a non-issue, and neither is optional in the way the historical recipes imply.
So: cure the legs properly, cool the finished confit quickly rather than leaving it on the counter overnight, keep it at refrigerator temperature throughout, and do not store it in a cupboard or a cellar because a book from another century says you can. If a jar has been left out for hours, has an off smell, or shows any gas or bubbling under the cap, it goes out.
Reheat confit thoroughly rather than warming it, and once a jar has been opened and legs removed, re-melt the fat, re-cover what is left, and use it sooner rather than later. Every time the cap is broken, the clock resets shorter.
The crisping is a separate operation
Nothing that comes out of the confit pot is brown, and the skin is soft. The crisping happens at serving time, from cold, and it takes about fifteen minutes.
Scrape most of the fat off the leg, then set it skin down in a dry, cold, oven-safe pan and bring it up over medium heat. Starting cold lets the remaining subcutaneous fat render before the skin sets, which is what gets it thin and crisp rather than thick and chewy. Eight to twelve minutes, without moving it, until the skin is deep brown.
Alternatively, skin up on a rack in a 400F oven for fifteen to twenty minutes, which is easier for six legs at once and slightly less crisp. Either way, the meat only needs heating through, since it has been cooked for six hours already. A duck breast is the opposite job and wants the opposite treatment.
Six ways a confit disappoints
Salty. The cure ran too long, or the legs were buried in salt rather than weighed. Weigh it, and rinse properly at the end.
Dry and stringy. The oven was too hot. Get a thermometer onto the shelf and drop the setting.
Tough after six hours. Older, larger legs sometimes need eight. Give it more time rather than more heat.
The skin will not crisp. Too much fat left on it, or a hot pan at the start. Scrape it, and start from cold.
It went off in the jar. Meat juices carried over under the cap, or a leg not fully covered. Strain, and check the coverage.
It tastes of nothing but duck fat. The cure was skipped or too light. The salt and the aromatics are where the flavor comes from, and the fat is a medium. A cassoulet built on undercured confit tastes flat all the way through.
Frequently Asked Questions
Can I reuse the fat?
Yes, several times, and it improves each time. Strain it through a fine sieve while warm, let it settle, and pour it off the layer of meat juice that collects underneath. Refrigerated, strained duck fat keeps for months, and it is the correct fat for roast potatoes.
What if I cannot buy duck fat at all?
Start with rendered pork fat, which is cheap and behaves identically, or a neutral oil. Purists object to oil and the finished leg is very close, particularly since the duck renders its own fat into the pot within two hours. What you should not use is olive oil or butter, both of which bring flavors that fight the duck.
Does this work for chicken or pork?
Yes. Chicken legs confit in about four hours at the same temperature and are excellent, though they are less collagen-rich so the transformation is smaller. Pork belly and pork shoulder both work and take longer. Goose is the classic alongside duck and follows the same clock.
Can I do it in a slow cooker?
The low setting on many slow cookers runs close to 200F, which is in range, and the shape of the pot is narrow and deep, which is exactly what you want for the fat. Check the actual temperature with a thermometer first, since the setting varies considerably between machines.
How long does it need to sit before eating?
It is good the day it is made and better after a week. The salt and aromatics continue to move through the meat while it sits under the fat, and the texture settles. Anything made for a cassoulet or a salad benefits from at least a few days.
