Rognons de Coq Farcis pour Entrées Froides, Garnitures, etc.

Ingredients

Equipment Needed

• •2-quart saucepan
• •Instant-read thermometer
• •Fine-mesh sieve
• •Piping bag with ½-inch plain tip
• •Wire rack and rimmed tray
• •Shallow 1½-quart timbale or oval serving dish

Instructions

1. 1

   Poach the rognons

   Bring the water and 1 teaspoon of the salt to a bare simmer in a small saucepan. Lower in the cleaned rognons and hold the water between 180 and 185°F (82 and 85°C), with only an occasional bubble, until they feel firm and their centers reach 165°F (74°C), about 8 to 12 minutes depending on size. A hard boil toughens their delicate flesh. Lift them onto a clean tray, pat dry, and refrigerate until cold, about 30 minutes.

   The source begins with cooked rognons. This gentle poach supplies that missing mise en place without changing the entry's sequence or flavorings.
2. 2

   Prepare the light gelée

   Measure 1½ cups (360 ml / 360 g) of the chicken stock. Sprinkle 2 teaspoons of the gelatin over ¼ cup (60 ml / 60 g) of that cold stock and leave it for 5 minutes. Warm the remaining stock until hot but not boiling, then stir in the softened gelatin and ¼ teaspoon of the salt until completely dissolved. Strain into a measuring jug and cool until it has the consistency of raw egg white but remains pourable. If it sets solid before you need it, stand the jug briefly in lukewarm water and stir. Do not boil it; boiling weakens its clean set.

3. 3

   Build the chaud-froid

   From the remaining 1 cup (240 ml / 240 g) stock, reserve 1 tablespoon (15 ml / 15 g) and sprinkle the final teaspoon of gelatin over it. Melt the chaud-froid butter over gentle heat, stir in the flour, and cook this pale roux for 2 minutes without letting it color. Whisk in the rest of the stock gradually, scraping into every corner, then simmer gently for 6 to 8 minutes until the sauce coats the back of a spoon. Add the cream and simmer for 2 minutes more. Remove from the heat, dissolve the softened gelatin in the sauce, and season with ¼ teaspoon salt and ¼ teaspoon white pepper. Strain and cool, stirring occasionally, to 82 to 86°F (28 to 30°C), when it should flow like light cream. If it sets too firmly, warm the bowl over barely warm water; if it runs thin, chill and stir it for several minutes. Ça se rattrape.

   Keep this chaud-froid white by cooking the roux without color. The source permits pink or white according to the service; white keeps this home-scale version focused on foie gras and clear gelée.
4. 4

   Make foie gras butter

   Beat the sieved foie gras and softened fresh butter together until completely smooth. Their weights are equal, exactly as the source requires. Add the remaining ¼ teaspoon white pepper and the final ½ teaspoon salt in two additions, tasting a cold dab before adding the last of the salt because prepared foie gras varies. Cold food needs assertive seasoning, but it must still taste of foie gras first. Transfer the mixture to a piping bag fitted with a ½-inch plain tip. If it becomes greasy or slack, chill it for 5 to 10 minutes and beat again; if it is too firm to pipe, warm the filled bag between your hands.

5. 5

   Shape and fill

   Cut each cold rognon in half lengthwise. Lay each half cut-side up and shave the thinnest possible sliver from its rounded underside so it sits without rocking; trim sparingly, because this small correction is what keeps the finished pieces steady under the gelée. Pipe a smooth, rounded ridge of foie gras butter along each cut face, using about 2 teaspoons per half. Arrange the 16 filled pieces on a tray and refrigerate for 20 minutes, until the filling is firm.

6. 6

   Mask the rognons

   Set the cold filled rognons on a wire rack over a tray. Stir the barely fluid chaud-froid, then spoon it from end to end over each piece, masking the filling and sides completely while leaving the trimmed underside free to stand. Let the excess drip away and refrigerate for 20 to 30 minutes, until the white coating feels firm and satin-smooth. If the mask slides off, either the rognons or the sauce was too warm. Scrape the loose coating back into the bowl, chill both for 10 minutes, gently rewarm the sauce only until it flows, and coat again.

7. 7

   Anchor under gelée

   Pour a thin layer of cool, fluid gelée into a shallow timbale or oval serving dish and refrigerate for 10 to 15 minutes, until tacky but not fully firm. Arrange the masked rognons filling-side up, close together without touching. Spoon just enough gelée around their bases to anchor them, chill for another 10 minutes, then pour the remaining gelée slowly down the side of the dish until the pieces are covered by about ¼ inch (6 mm). The gelée must be cool and fluid. If a piece floats, stop pouring, lift it out, chill the anchor layer until firmer, and reset it. If warm gelée clouds the white coating, spoon it away, rechill the rognons, and cool the remaining gelée further before continuing.

8. 8

   Chill and serve

   Cover the dish without touching the surface and refrigerate for at least 4 hours, preferably overnight, until the gelée trembles but holds a clean spoon mark. Serve directly from the low timbale while thoroughly cold, allowing four pieces per guest. Keep the dish chilled until it reaches the table and return leftovers to the refrigerator within 2 hours. À table!

Chef Tips

• •Rognons de coq are rooster testicles, not poultry kidneys. Order them from a licensed poultry farm, specialist butcher, or offal supplier, and insist that they arrive cleaned and properly chilled. Calf or lamb kidneys don't share their shape or delicate texture and aren't an honest substitute.
• •Use plain cooked foie gras from a lobe or an unsweetened terrine, then press it through a sieve. Foie gras mousse already contains added fat and liquid, so combining it with an equal weight of butter produces a filling too soft to hold.
• •Clarity begins with the stock. Chill it first and remove every trace of surface fat; melted fat makes the gelée cloudy, while the measured gelatin supplies the light set once provided by an always-ready professional stockpot.
• •Serve with brut Champagne or a taut, dry white wine. The acidity clears the richness of foie gras and butter without bullying the mild rognons.

Advance Preparation

• •The rognons can be poached and chilled a day ahead. Keep them covered in the refrigerator and split them only when you are ready to fill.
• •The gelée and chaud-froid can also be prepared a day ahead and chilled separately. Return each to fluid form over lukewarm water, never direct high heat.
• •Finish the assembled dish 8 to 24 hours before serving. Keep it covered and refrigerated, and eat within 2 days because both poultry offal and foie gras are highly perishable.

Frequently Asked Questions

Nutrition Information

1 serving (about 260g)