Bombe Coppélia

Ingredients

Equipment Needed

• •1.2-litre metal bombe mould or 18 cm metal bowl
• •Small heavy saucepan, preferably 10 to 12 cm across
• •Sugar or instant-read thermometer
• •Electric hand mixer or stand mixer
• •Food processor or sturdy spice grinder
• •Silicone baking mat
• •Chilled serving platter

Instructions

1. 1

   Chill the mould

   Set a 1.2-litre metal bombe mould or bowl in a freezer at 0°F (-18°C) for 30 minutes. Chill the serving platter as well. Move the coffee ice cream to the refrigerator for 15 minutes before lining; it should yield to a spoon but remain dense and cold, with no liquid around its edges.

   Do not line the mould with plastic. It leaves folds across the bombe and traps pockets of air; the brief unmoulding method at the end releases it cleanly.
2. 2

   Clothe with coffee ice

   Adapt the clothing-the-mould method from Another Method of Preparing Aspics de Filets de Soles (No. 916): press about two-thirds of the coffee ice cream across the bottom and sides in a smooth layer 1 to 1.5 cm thick, turning the cold mould as you work with the back of a chilled spoon. Freeze for 20 minutes, inspect for thin patches, and fill them with more ice cream. Keep the remaining ice cream frozen for the base. If the lining slides, it has softened too far; freeze the mould for 10 minutes, then press the layer back into place.

3. 3

   Make the pralin

   Toast the almonds and hazelnuts in a dry heavy pan over medium heat until fragrant and lightly coloured, then tip them onto a plate. Put the 50 g sugar and 15 ml water in the pan and cook without stirring until the caramel turns a clear deep amber. Add the warm nuts, turn them through the caramel, and pour everything onto a silicone mat in one thin layer. If the caramel clumps around the nuts, return it to the lowest heat and turn gently until fluid again. Let it cool until absolutely hard and cold, about 30 minutes, then break it up and pulse it into fine, sandy pralin. Stop before the nuts release enough oil to make a paste; if that happens, chill the paste and use it cold, accepting a slightly denser centre.

4. 4

   Whip the pâte à bombe

   Beat the yolks at medium speed until pale and slightly thickened. Meanwhile, cook the remaining 50 g sugar with 30 ml water in the smallest heavy saucepan you own, without stirring after it boils, until the syrup reaches 244°F (118°C). With the mixer running, pour the syrup in a thin stream down the inside of the bowl, keeping it clear of the whisk. Beat at high speed until the pâte à bombe is thick enough to fall in a ribbon and the bowl no longer feels warm, 6 to 8 minutes. It must be below 75°F (24°C) before the cream enters; if it remains warm, set the bowl over ice and continue whisking.

5. 5

   Fold the centre

   Whip the cold cream to soft peaks that hold their curve without looking grainy. Fold one-third into the cooled pâte à bombe to loosen it, then fold in the rest with broad strokes. Add the cold, finely ground pralin and fold only until evenly dispersed. Pralined means treated throughout with pralin, not merely sprinkled with nuts. If the pralin feels warm, stop and chill it before folding. If it has already gone in and the cream begins to slacken, set the bowl over ice and fold gently just until some body returns, then fill the mould at once. The centre may be a little denser, but it will set. Ça se rattrape.

6. 6

   Fill and seal

   Spoon the pralined pâte à bombe into the frozen coffee shell, pressing gently toward the sides so no air pockets remain. Stop about 1 cm below the rim; if there is extra filling, freeze it separately in a small cup. Soften the reserved coffee ice cream just enough to spread, then close the exposed base with an even layer and scrape it level with the mould. Cover tightly and freeze for at least 6 hours, preferably overnight, until completely firm.

7. 7

   Unmould and serve

   Lower only the outside of the mould into lukewarm water for 5 seconds, dry it, and invert it onto the chilled platter. If it does not release, wrap the mould briefly in a warm towel and try again; do not leave it in water long enough to melt the coffee shell. If the surface becomes soft before release, return the still-moulded bombe to the freezer for 20 minutes. Cut with a knife dipped in hot water and wiped dry between slices, then serve immediately. À table!

Chef Tips

• •Choose a dense, cream-based coffee ice cream with a clear roasted-coffee bitterness. A very airy or reduced-fat ice cream makes a weak shell that softens before the centre can be cut.
• •The dry pralin is essential. Commercial praline paste contains more released oil and produces a heavier centre; if paste is all you have, use 1/3 cup (80 ml / 90 g), keep it thoroughly cold, and expect a closer texture.
• •Use a metal mould or mixing bowl. Metal freezes the coffee lining quickly and responds immediately to the warm towel when you unmould; thick glass is slow in both directions and may crack under a sudden temperature change.
• •Serve Bombe Coppélia without stray decorations. Espresso or a small glass of Cognac belongs beside it, not poured over it, so the contrast between coffee ice and pralined centre remains clear.

Advance Preparation

• •The pralin can be made up to one week ahead. Keep it airtight in a cool, dry cupboard and grind it shortly before assembling so the nuts remain fragrant.
• •The complete bombe is best assembled the day before serving. Once frozen solid, wrap the mould tightly to protect the coffee ice from freezer aromas; it holds well for three days.
• •Chill the serving platter and dessert plates for 30 minutes before unmoulding. The cold porcelain buys several calm minutes at the table without changing the texture of the centre.

Frequently Asked Questions

Nutrition Information

1 serving (about 145g)