Once you’ve got that going, it’s already time to set up the bed on which your ducks will roast. Slice the onion thinly, roughly chop the celery and carrot, and set in the roasting pan with your giblets (sans liver), wing bones, and chicken backs. Roast these for 35-40 minutes once your oven has reached 450°. Remove the pan from the oven, turn the oven down to 250°, and rotate every piece of vegetable and bird part. Add one cup of broth, and scrape any blackened bits from the bottom and sides of your roasting pan.

Remove the birds from their brine, and dry inside and out with paper towels. Because we slow-cook the bird for hours, we really dont’ have to worry about making the skin as dry as possible for crisping. Sew up the back end with poultry needles and butcher twine. Do the same with the front cavity. The point is to seal the carcass to prevent the Venturi effect from expediting the cooking. You want your ducks to roast very slowly under a low heat.

Rub coarse salt and pepper into both sides of your ducks. Don’t be shy with your salt. To paraphrase one German author, a poorly salted bird tastes vapid. Set breastside down on your partially roasted vegies and giblets. Roast for four (yes, four) hours at 250°, turning every hour.

After four hours, your birds should be breastside up. Remove the pan from the oven and kick that oven back up to 450°. Flip the birds so they’re breastside down, and return to the oven. Yes, your oven will not yet be at 450°. You’ll be cooking by color from now on. Roast until the backs of the birds are dark and crisp, maybe 40 minutes. Flip the birds again so they’re breastside up, add another cup of broth, scrape all the rich dark bits from the sides of the pan into the broth, and roast another 30 minutes or until the skin on the breasts are dark and crisp. You may need more time, you may need less. Remove the birds and set on a cutting board to rest.

Phew! You’ve made it this far. You have ducks with flesh that’s tender and moist, surrounded by an amazing crisp skin, almost as if fried. Now on to the gravy.

Put the roasting pan on the stovetop over medium high heat, add the last cup of broth, and scrape, scrape, scrape, those black bits on the sidewalls into the drippings. This is what makes your gravy dark and gives it all its flavour. Cook, stirring and scraping constantly, for about 10 minutes.

Strain away the vegetables and bird parts into a fat separator. Give it a couple of minutes for the fat to rise to the top then pour off the gravy into a saucepan. Mix about ¼ cup of this gravy with the 2 Tablespoons of cornstarch, and then stir that into the saucepan of gravy. Bring to a quick, short boil to thicken. Remove from stovetop.

Cut each duck in half, removing back and neck, with poultry shears. Sauce four plates with ample gravy and set half bird atop each.

The odd on-again off-again cooking method is because we have three conflicting goals. We want a tender, moist bird, with crispy skin, and a rich, chocolate-dark gravy. If we were to roast the birds at high heat (say 450°) we’d have a crisp skin and a dark gravy, but the meat will be tough and difficult to carve from the bone. If we cook at a low heat, we’ll have a moist bird and much of the fat under the skin will have rendered, but the skin will be soggy and the gravy weak. If we start off with the high-heat cookery, the birds will be quickly colored, and we’ll have no chance to correct or adjust for the remaining 4+ hour cooking time. And if we save all the high heat for the finishing, our ducks will grow cold resting while we carmelize the vegies and make the gravy.

So, repeated experimentation has proven that the best compromise is to begin carmelizing the vegies for the gravy at the start, then slow roast the birds, then kick up the heat to crisp the skin and finish the gravy.

Doesn’t brining affect the ability to crisp the skin? Wouldn’t saturating the skin with water make it more difficult to dry out and crisp? Surprisingly, no. And this was an easy test: lay a bird on its side and brine only that half. Any difference in skin crispiness when roasted? Nope. But do we even need to brine? Yessir, our testers consistently preferred the moistness and flavour of brined bird.

What about pricking the skin, maybe even with every turn, to let the fat render? Wouldn’t that make a crisper skin? Another easy test: prick one side and not the other. Any difference? Again, the answer is no.

What about chemical crisping agents, like tossing a little baking powder into the salt and pepper rub? Or blanching the whole bird alá Peking Duck? The first is a modernist cheat, like rubbing caramel coloring or soy sauce into the skin to artificially brown it. And the second? Good lord, isn’t this recipe complex enough?

How about basting the bird? What, coat the skin with water when we’re trying vigorously to dry it out? Haven’t you been paying attention?

This dish is a Bavarian holiday speciality. Called Bauernente (‘farmer’s duck’), it is reserved for the autumn Kirchweih holiday. Goose may also be cooked this way for Kirchweihsonntag or Christmas.

You could save yourself some time by making the gravy a day ahead. Roast backs, wing tips, and vegies at 450° for 1½-2 hours. Deglaze with broth, scraping browned bits every half hour. Defat and boil down as per the rest of the recipe. It won’t be quite as rich, but it’ll be a gravy you can keep onhand and use for other recipes.

Don’t discard those blackened backs and caramelized vegies you’ve spent all day preparing. Nor the neck from the roast, nor all your family’s scraps. They all go into a Dutch cooker the next day with some fresh vegies to make the richest chicken broth you’ve ever seen. Which you should stick in the freezer use in place of canned beef broth the next time you make this dish.