Filbert Ice-cream

Ingredients

Equipment Needed

• •Small rimmed baking pan
• •Food processor or large mortar and pestle
• •2-quart (2-litre) heavy saucepan
• •Fine-mesh sieve
• •Flexible heatproof spatula
• •Instant-read thermometer
• •Medium metal bowl and larger bowl for an ice bath
• •1½-quart (1.4-litre) ice-cream machine

Instructions

1. 1

   Torrify the filberts

   Heat the oven to 325°F (165°C). Spread the filberts in one layer on a small rimmed pan and toast for 7 to 10 minutes, shaking the pan once, until their skins deepen slightly and a cut nut is pale honey-gold inside. Their fragrance should be warm and sweet, never sharp or coffee-like. Cool for 5 minutes, then rub away only the skins that slip off readily. If one or two nuts have scorched, remove them and replace their weight; if the whole batch is brown within, begin again. Bitterness cannot be strained out.

2. 2

   Pound a fine paste

   Measure 3 tablespoons (45 ml / 46 g) from the milk and set the rest aside. Pulse the warm filberts in a food processor until finely ground, then add the measured milk a spoonful at a time and continue until you have a thick, fine paste. Scrape the bowl often. Stop if oil begins pooling around the blade, then work in another spoonful taken from the remaining milk to bring the paste together. A mortar and pestle gives the same result with more elbow, but no greater virtue.

3. 3

   Infuse twenty minutes

   Bring the remaining milk to a full boil in a heavy saucepan, then take it off the heat at once. Scrape in every bit of filbert paste, whisk until evenly dispersed, cover, and infuse for exactly 20 minutes. This hot-milk infusion is the heart of the formula. A longer steep does not make the flavour nobler; it begins drawing bitterness from the red skins.

4. 4

   Strain and rewarm

   Pass the infused milk through a fine-mesh sieve into the rinsed saucepan. Press the paste steadily with a flexible spatula to recover the fragrant milk, but don't force coarse grit through the mesh. Reserve 2 tablespoons (30 ml / 30 g) of the cold cream in a metal bowl set over ice, then add the remaining cream to the saucepan. Warm gently until small bubbles gather around the edge, without letting it boil.

5. 5

   Cook the crème anglaise

   Whisk the yolks and sugar in a bowl just until smooth and slightly lighter. Pour in one-third of the hot filbert milk while whisking, then return everything to the saucepan. Cook over low heat, stirring constantly along the floor and into the corners with a flexible spatula, until the crème anglaise reaches 175 to 180°F (79 to 82°C) and coats the back of the spatula. Draw a finger through it; the line should remain clean. Never boil it.

6. 6

   Rescue and chill

   Immediately strain the crème anglaise into the reserved cold cream over the ice bath. If you see the first fine grains of curdled yolk, pour it onto that cold cream at once, blend briefly until smooth, and then strain. Ça se rattrape when caught early. Stir over the ice for about 15 minutes, until thoroughly cool, then cover and refrigerate for at least 2 hours, or overnight, until the base is no warmer than 40°F (4°C). A warm base churns slowly and forms coarse crystals.

7. 7

   Churn until softly set

   Stir the cold base, pour it into the prepared ice-cream machine, and churn according to the machine's directions, usually 20 to 25 minutes. Stop when the glace holds soft ridges and falls from the paddle in a heavy fold. If it remains loose after 30 minutes, stop before the cream turns grainy, return the base to the cold, refreeze the machine bowl completely, and churn again.

8. 8

   Firm and serve

   Pack the freshly churned glace into a shallow freezer container, press parchment directly against the surface, cover, and freeze for about 2 hours for a firm, scoopable texture. Let it stand at room temperature for 5 to 10 minutes before serving, just until a spoon enters without a struggle. Serve generous scoops with nothing scattered over them. The clean filbert perfume is the finish. À table!

Chef Tips

• •Buy raw, unsalted filberts. If the market labels everything simply as hazelnuts, choose plump nuts with tight red-brown skins and no stale or paint-like smell. The name matters less than a fresh nut treated carefully.
• •Cut one filbert open as the batch toasts. The exterior skin darkens before the centre is ready, so the interior colour is the honest judge: pale honey-gold, not mahogany.
• •Don't add vanilla, praline, coffee, or liqueur. The source formula builds its flavour from filberts infused in boiled milk, and extra perfume would cover the distinction it works to preserve.
• •Homemade glace hardens more firmly than a commercial ice cream. A shallow container and a short temper before scooping restore its creamy texture without changing the formula.

Advance Preparation

• •If the machine uses a freezable canister, freeze it for at least 24 hours before churning. A partly frozen bowl leaves the base loose and encourages coarse ice crystals.
• •The strained crème anglaise can be prepared up to 2 days ahead and kept covered in the cold. Churning an overnight-chilled base gives the smoothest texture.
• •The finished glace keeps well for about 1 week in an airtight freezer container with parchment pressed against its surface. Let it soften briefly before scooping.

Frequently Asked Questions

Nutrition Information

1 serving (about 110g)