Date:  October 26th, 2025 10:50 PM
Author: brass jap
Short answer: yes. There’s a strong classical precedent for sauces made directly from a duck’s body (carcass, neck, wings, skin, giblets). Examples include:
 	•	#1 Duck jus / fond brun de canard — a deeply reduced stock from roasted bones and trimmings.
 
	•	Sauce bigarade — orange-based pan sauce finished with duck jus.
 
	•	Salmis — game-bird sauce built from the roasted carcass and giblets, nappé over the carved meat.
 
	•	Canard à la presse (Rouennaise) — a blood-thickened sauce extracted from the crushed carcass (the “pressed duck” made famous in Rouen/Paris).
 
 
Below is a practical, home-kitchen method that gets you a proper “from-the-duck” sauce without special gear, plus an optional Rouennaise finish if you want to go fully classical.
 
 
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Whole-Duck Body Sauce (rich duck jus)
 
 
Yield: ~1½–2 cups (360–480 ml) sauce
 
Time: 2½–3½ hours (active ~30 min)
 
Use with: roasted or pan-seared duck breasts/legs
 
 
What you’ll use from the duck
 
	•	Carcass (back, rib cage, wishbone), neck, wings, and wingtips
 
	•	Skin/fat trimmings
 
	•	Giblets (heart & gizzard for the pot; reserve liver for finishing)
 
 
Ingredients
 
	•	1 whole duck’s roasted bones/trimmings (see Steps)
 
	•	1 medium onion, chopped
 
	•	1 small carrot, chopped
 
	•	1 small celery stalk, chopped
 
	•	1 tbsp tomato paste
 
	•	1 cup (240 ml) dry white wine or dry sherry (red wine works too; will be deeper)
 
	•	4–5 cups (1–1.25 L) water (enough to cover)
 
	•	1 small garlic clove, smashed
 
	•	6–8 black peppercorns
 
	•	2 sprigs thyme + 1 bay leaf
 
	•	Optional but great: 1 strip orange peel (no pith) or 1 star anise (not both unless you like it aromatic)
 
	•	1 small shallot, minced (for the finish)
 
	•	1–2 tsp sherry vinegar or lemon juice (to balance)
 
	•	2–3 tbsp cold unsalted butter or 1–2 tbsp duck fat (for mounting)
 
	•	Optional gloss: ½–1 oz (15–30 g) raw duck liver (see finish)
 
 
Method
 
	1.	Break down & reserve:
 
Remove breasts and legs to cook separately. Keep the carcass, neck, wings, wingtips, heart, and gizzard. Save the liver for later (don’t simmer it in the stock; it can make it muddy).
 
	2.	Roast the body for flavor:
 
Heat oven to 425°F / 220°C. Spread the carcass, neck, wings, wingtips, heart, and gizzard on a rimmed sheet. Roast 35–45 min until well browned. Toss the chopped onion, carrot, celery with a little rendered duck fat (or neutral oil) and add to the tray for the last 10–15 min. Smear tomato paste on the tray in the last 5 min to lightly caramelize it.
 
	3.	Deglaze the tray:
 
Move everything to a pot. Pour ½ cup of the wine onto the hot tray; scrape up the fond and add to the pot.
 
	4.	Simmer the stock:
 
Add water to cover by ~1 inch, the garlic, peppercorns, thyme, bay, and orange peel or star anise if using. Bring just to a boil, then simmer very gently uncovered 90–120 min, skimming. You’re extracting gelatin and roasted flavors; avoid a rolling boil.
 
	5.	Strain & reduce:
 
Strain through a fine sieve, pressing gently. Return liquid to a clean saucepan and reduce to about 2 cups / 480 ml. Taste: it should be savory and slightly sticky.
 
	6.	Build the sauce base:
 
In a small pan, render 1–2 tbsp of your duck skin trimmings over medium heat until lightly browned; pour off all but 1 tsp fat. Add the minced shallot, sweat 1–2 min. Add remaining ½ cup wine, reduce by half. Add the reduced duck stock/jus and simmer to nappe (coats a spoon), ~5–10 min.
 
	7.	Finish (choose one):
 
	•	Classic mount: Off heat, whisk in 2–3 tbsp cold butter (or 1–2 tbsp duck fat) to gloss. Balance with 1–2 tsp sherry vinegar or lemon. Season with salt.
 
	•	Salmis-style liver gloss (deeper, richer): Off heat, blender-whirr in ½–1 oz (15–30 g) raw duck liver with a knob of cold butter, then return to the pan and warm gently (do not boil) until just thickened and satiny. Adjust acidity/salt.
 
	8.	Hold & serve:
 
Keep warm, not boiling. Spoon over sliced duck breasts/legs or anything that wants a deep, meaty glaze.
 
 
Notes & variations
 
	•	Pressure cooker option: After roasting (Steps 2–3), cook at high pressure 45 min, natural release, then proceed to reduce and finish.
 
	•	Orange/bigarade tilt: Add a few fine strips of orange zest in Step 6 and finish with 1–2 tbsp fresh orange juice and a splash of Grand Marnier instead of (or in addition to) vinegar.
 
	•	Green peppercorn: Stir in drained brined green peppercorns at the end.
 
 
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Optional: Rouennaise (Pressed-Duck–style) Finish
 
 
If you want the famous deep mahogany, slightly gamey sauce thickened with blood:
 
 
What changes:
 
	•	Reduce your strained duck stock to ~1 cup / 240 ml (more concentrated).
 
	•	In Step 6, use cognac + red wine (¼ cup each) instead of white wine.
 
	•	Stabilize fresh duck blood (or food-grade pig’s blood if that’s what you can source) by whisking 3–4 tbsp (45–60 ml) blood with 1 tsp red wine vinegar.
 
	•	Off the heat, slowly whisk the blood into the hot (but not boiling) sauce, then add 2 tbsp cold butter. Return to very low heat and warm to ~150–160°F / 65–70°C just until glossy and nappant. Do not boil or it will curdle.
 
 
Food-safety & practicality: Use only fresh, food-grade blood from a reputable source; keep it cold; add acid; and never boil the blood-finished sauce. If blood isn’t available, the liver gloss method above is an excellent, safer stand-in that evokes a similar luxurious body.
 
 
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Why this works
 
 
You’re extracting gelatin and roasted flavors from the duck’s bones, skin, and connective tissues, then concentrating and emulsifying them. That’s precisely how classic French “body-from-the-bird” sauces are built, whether finished simply with butter, enriched with liver (salmis), brightened with citrus (bigarade), or thickened with blood (Rouennaise).
(http://www.autoadmit.com/thread.php?thread_id=5790225&forum_id=2:#49377601)