INSPIRED BY the chocolate palet d’or, a bonbon created by French chocolatiers at the turn of the century, we have reinvented this delicacy as a dessert hidden inside a gold-dusted, chocolate-glazed orb. Our own palet d’or reveals a classic gianduja filling, the historical hazelnut paste mixed with chocolate. A hazelnut-coated hazelnut ice cream extends the theme even further.
Set the sheet of acetate on a smooth, flat surface. With an offset spatula, evenly spread tempered chocolate across the sheet to approximately 1 millimeter thickness. Run a -inch-gauged chocolate comb crosswise across the acetate to form 12-inch-long strips. Allow the chocolate to cool slightly, about 4 minutes, then wrap the sheet of acetate, chocolate side out, around the tube; secure with tape. Allow to set for 24 hours before removing.
For the Praliné Ice Cream
In a small bowl, mix 1 tablespoon of the sugar with the ice cream stabilizer. In a medium saucepan, combine the milk, cream, trimoline, and milk powder and place over medium heat. Once the milk mixture reaches 122°F, whisk in the sugar-stabilizer mixture. Continue to heat until the milk mixture begins to simmer; remove from the heat. In a medium heatproof bowl, whip the egg yolks with the remaining 1 tablespoon sugar. While whisking, gradually pour half of the hot cream into the egg yolk mixture. Gradually whisk the mixture back into the saucepan. Return the saucepan to medium heat and cook slowly, while whisking, to 185°F. Remove from the heat and whisk in the praline paste until well combined. Pass the mixture through a fine-meshed sieve into a bowl set over ice. Stir until well chilled and spin in an ice cream machine according to the manufacturer’s instructions.
For the Hazelnut Coating
Line a baking sheet with a Silpat. In a medium saucepan, melt the sugar with 1 tablespoon water and heat, until lightly caramelized, to 250°F. Stir in the hazelnuts with a wooden spoon. Continue cooking the hazelnuts over medium heat, stirring until the sugar turns from a frosted white color to a glossy caramel. Transfer the nuts to the prepared baking sheet and spread into an even layer. Cool at room temperature for about 30 minutes, until hardened.
Transfer the nuts to a food processor fitted with a blade and pulse into crumbs. Transfer the nuts to a shallow baking dish. Scoop a ball of ice cream into the nuts and roll until evenly coated; transfer to a plate and return to the freezer. Repeat the process to make 8 scoops.
For the Praline Sauce
Soak the gelatin in ice water for 10 minutes; squeeze dry. In a small saucepan, bring the milk to a simmer. Stir in the gelatin to dissolve, then mix in the praline paste. Cool, and transfer to a piping bag. Reserve, chilled.
For the Chocolate Sablé
In a large bowl, whisk the powdered sugar and vanilla seeds until well incorporated and no lumps remain. Add the almond flour, cornstarch, flour, and salt and whisk to combine. In the bowl of an electric mixer fitted with a paddle, mix the butter until creamy. On low speed, gradually add the dry ingredients to the butter and mix until combined. Scrape the bowl with a rubber spatula, then add the egg and mix on medium speed until combined. Scrape the dough from the bowl, pat into a rectangular shape, wrap in plastic wrap, and refrigerate for at least 1 hour or up to 3 days.
Preheat the oven to 350°F. Set the dough on a sheet of parchment paper, top with another paper, and roll into a -inch-thick rectangular sheet. Slide the bottom sheet of parchment along with the dough onto a baking sheet and remove the top layer of paper. Bake for 4 minutes, or until a light golden brown. Remove from the oven and cool at room temperature. When the sablé has cooled, break it into small chunks.
Fill one-third of a small saucepan with water and bring to a simmer. Place the chocolate in a heatproof bowl and set it over the water. Heat the chocolate, stirring, until melted and it reaches 104°F.
Transfer the chocolate and sablé chunks to a standing electric mixer fitted with a paddle attachment and mix on medium speed until the sablé is broken down into crumbs. When the chocolate and crumbs have come together, scoop onto a sheet of acetate, top with another sheet, and roll to a thickness of 2 millimeters. Transfer to a flat tray and refrigerate until the chocolate is set. With eight 3-inch-wide ring cutters, cut discs from the gianduja crust. Keep the crust in the bottoms of the rings, chilled.
For the Dark Chocolate Crémeux
In a heatproof bowl, whisk the egg yolks with the sugar until smooth. In a medium saucepan, bring the milk and cream to a simmer. While whisking, gradually pour half of the hot milk into the egg yolk mixture. Gradually whisk the mixture back into the saucepan. Return the saucepan to the heat and cook slowly while whisking until it reaches 185°F. Put the chocolate in a high-sided container such as a pitcher. Pour the hot cream mixture through a fine-meshed sieve over the chocolate and rest for 1 minute. Use a hand blender to mix until smooth, keeping the mixer head submerged to avoid air bubbles. Cover and refrigerate for at least 3 hours or overnight, until set. Transfer the crémeux to a piping bag and pipe ¼-inch-high discs onto the tops of the sablé discs inside of the metal rings, leaving a ¼-inch gap between the crémeux and the rings. Refrigerate the rings.
For the Dark Gianduja Pâte à Bombe
Soak the gelatin sheets in ice water for 10 minutes; squeeze dry. In a medium bowl with a whisk, whip ¾ cup plus 2 tablespoons of the heavy cream to soft peaks. Cover and keep chilled.
In the bowl of an electric standing mixer, whisk to combine the yolks, egg, and sugar with 2 tablespoons water. Place the chocolate in a separate heatproof bowl and set aside.
Fill half of a medium saucepan with water and bring to a simmer. Set the mixer bowl with the egg mixture over the simmering water and heat, while whisking, until it reaches 185°F. Transfer the bowl to the electric mixer fitted with a whisk and continue whipping on high speed until the eggs cool to 104°F.
While the egg mixture is whipping, place the bowl of chocolate over the pot of simmering water and heat, stirring, until it is melted and reaches 113°F; remove from the heat. Transfer the remaining heavy cream to a small saucepan, bring to a simmer, remove from the heat, and stir in the gelatin until dissolved. Stir into the melted chocolate until combined.
Whisk one-third of the egg mixture into the chocolate. Fold in the remaining egg mixture in 2 batches with a rubber spatula until just combined. Fold in the reserved whipped cream until no streaks remain.
Remove the rings from the refrigerator and divide the mousse inside them to reach the rims. Use an offset spatula to spread the mousse so it is flush against the top of the molds. Freeze until the mousse is solid, about 4 hours.
Remove the mousse rings from the freezer. Warm the sides of the rings with your hands and pop out the palets. Set the frozen palets on a baking rack set over a baking sheet 1 inch apart; return to the freezer. Transfer the glaze to a heatproof bowl and warm in a microwave or over a saucepan of simmering water until it reaches 95°F. Ladle the chocolate glaze over the palets to coat. Refrigerate the palets for 2 hours so the glaze sets and the interior thaws. Dust the palets with powdered gold.
For each serving, stand 2 dark chocolate rings on a plate in a crisscross pattern and, with an offset spatula, slide a palet into the center. Dot the plate with praline sauce and set a scoop of hazelnut-coated ice cream on the side.