Mousse d’Écrevisses

Ingredients

Equipment Needed

• •Broad 3-quart (2.8 L) sauté pan with lid
• •Kitchen shears
• •Heavy rolling pin and folded kitchen towel
• •Sturdy mortar and pestle or powerful blender suitable for hard ingredients
• •Fine-mesh tamis or sturdy fine sieve
• •Two nesting metal bowls for the ice bath
• •Whisk or hand mixer
• •1½-cup (360 ml) Charlotte mould or smooth bowl
• •Flexible spatula

Instructions

1. 1

   Ready mould and ice

   Set a smooth 1½-cup (360 ml) Charlotte mould or bowl over ice. For the book’s transparent finish, clothe the mould with about 2 tablespoons of the garnish jelly, rocking it over the ice until a thin, even film sets. This is the method carried in Another Method of Preparing Aspics de Filets de Soles (No. 916) and Mousse de Homard Moulée (No. 957). Dip four truffle rounds in fluid jelly and fix them against the coated sides. For a simpler release, line the mould closely with food-safe plastic wrap and set all the garnish jelly aside for chopping.

   Prepare the mould before touching the mousse. Once jelly and cream meet over ice, the mixture begins setting and will not wait politely while you search for a bowl.
2. 2

   Cook the crayfish

   Spread the Mirepoix (No. 228) across a broad, lidded sauté pan and arrange the crayfish over it. Cover and cook over medium-high heat for 6 to 8 minutes, shaking the pan frequently, until the shells are scarlet and the tail flesh is pearly opaque and reaches 145°F (63°C). If the mirepoix threatens to catch before the crayfish are cooked, add 1 tablespoon (15 ml) cold water, cover again, and let that small amount cook away. Transfer everything to a tray and cool only until the shells can be handled.

3. 3

   Shell and trim

   Twist off the tails, peel them, remove the dark intestinal threads, and pick any meat from the claws. Cut all the meat into fine dice and refrigerate it immediately. Reserve the four finest body carapaces, trim their uneven undersides with kitchen shears, rinse away any loose matter, and dry them well. From the remaining heads remove the gritty stomach sacs and feathery gills, then crush the cleaned shells inside a folded kitchen towel with a rolling pin.

4. 4

   Pound the shell base

   Put the crushed shells and all the cooked mirepoix into a sturdy mortar or powerful blender. Pound or pulse them to a fine, damp rubble before adding the unsalted butter, Red Colouring Butter (No. 142), cold fish velouté, and the 2 tablespoons plus 1 teaspoon of fluid fish jelly. Continue until the mixture becomes a thick coral paste. Work in short pulses if using a machine, and stop if its motor labours; crush the shells more finely by hand before continuing.

5. 5

   Rub through sieve

   Rub the paste firmly through a tamis (fine-mesh sieve), scraping the smooth purée from its underside as you work. Pass it a second time through the clean sieve or damp muslin. This cannot be shortened: one sharp fleck of shell ruins the mousse, so discard the dry grit rather than forcing it through. Transfer the perfectly smooth purée to a chilled metal bowl, taste it, and add only as much salt as it needs.

   A blender extracts the shells’ flavour and colour, but the tamis makes the mousse safe and silken. The machine assists the pounding; it never replaces the sieve.
6. 6

   Cool over ice

   Nest the bowl of purée in a larger bowl of ice and stir continuously for 2 to 3 minutes. Stop when the mixture feels thoroughly cold and the whisk leaves a fleeting trace, while the purée still flows from a spoon. If jelly begins setting around the edge in threads or little lumps, lift the bowl from the ice and whisk it briefly over barely warm water until smooth, then return it to the ice. Ça se rattrape.

7. 7

   Fold cream and tails

   Reserve 1 tablespoon (15 ml) of the liquid cream. Whip the remainder only until it falls from the whisk in soft, lazy folds without holding a peak. This is half-beaten cream, not stiff cream. If it turns grainy, whisk in the reserved liquid cream to smooth it; otherwise stir that reserved cream into the cold shellfish base. Fold one-third of the whipped cream into the base to lighten it, then fold in the remainder and the diced crayfish tails. Keep the bowl over ice, but lift it away if the edges begin setting before the tails are evenly distributed. If the finished mousse remains loose, stir it gently over ice for another minute.

8. 8

   Mould and chill

   Reserve about ¼ cup (60 ml) of mousse and divide it among the four cleaned carapaces. Fill the prepared mould with the remainder, smooth the top, and tap it once against a folded towel to release large air pockets. Dip four truffle rounds in fluid jelly and place one on each filled carapace. Cover both mould and shells, then refrigerate at 40°F (4°C) or colder for at least 3 hours. Pour the remaining garnish jelly into a shallow dish and chill it until firm.

9. 9

   Turn out and serve

   Dip a jelly-clothed mould in warm water for 2 seconds, dry its outside, and invert it onto a chilled serving dish. If it refuses to release, repeat for 1 second rather than warming it continuously. For a lined mould, invert and peel away the wrap. Should the mousse soften or slump, return it to the mould and chill it for 30 minutes before trying again. Chop the set garnish jelly, arrange it around the base, and stand the four filled carapaces almost upright in it. Dip the remaining truffle rounds in fluid jelly and set them in a small crown on top. Serve cold with small plates and spoons. À table!

Chef Tips

• •Whole crayfish are essential because the shells provide the mousse’s colour and much of its flavour. When fresh crayfish are unavailable, choose whole frozen raw crayfish and thaw them overnight in the refrigerator. Tail meat alone cannot do the same work.
• •Have the fish velouté and fish jelly made, cooled, and ready before beginning. Plain fish stock cannot replace either one: velouté supplies body, while the jelly sets the mousse cleanly enough to slice.
• •Do not replace Red Colouring Butter (No. 142) with food dye or paprika. The shell butter carries crayfish flavour as well as colour, and that double purpose is why the classical preparation belongs here.
• •The second pass through the tamis is not ceremony. Shell fragments can hide in a purée that looks smooth, and no amount of cream will make one pleasant under the teeth.
• •Take the mousse from the refrigerator about 5 minutes before serving, no longer. A dry Champagne or a mineral white Burgundy has enough brightness for the cream without covering the crayfish.

Advance Preparation

• •Prepare the Mirepoix (No. 228), Red Colouring Butter (No. 142), fish velouté, and fish jelly up to 2 days ahead and keep them covered in the refrigerator. Bring the shell butter only to a cool, pliable consistency before pounding.
• •The finished mousse and filled carapaces can be moulded up to 24 hours before serving. Keep them tightly covered so the cream does not absorb refrigerator odours.
• •The mould may be clothed with jelly and decorated with truffle earlier on the day of assembly. Keep it over ice or refrigerated until the mousse is ready.
• •Do not freeze the mousse. Freezing damages the cream emulsion and releases water from the jelly as it thaws.

Frequently Asked Questions

Nutrition Information

1 serving (about 100g)