Dark Chocolate Mousse with Candied Hazelnuts

In a stand mixer fitted with the whisk attachment, whip the heavy cream on medium-high speed until soft peaks form (the cream should be pillowy but not stiff), about 2 minutes. Transfer the whipped cream to a bowl and put it in the refrigerator while you make the chocolate custard.

Put the chocolate in a large bowl and set a fine mesh strainer over the bowl.

In a small bowl, whisk together the egg yolks, sugar, and corn syrup and set the bowl on a kitchen towel.

In a small saucepan, heat the milk over low heat just until tiny bubbles form (do not boil), 5 to 7 minutes. Very slowly pour about a quarter of the hot milk into the egg mixture, whisking constantly to prevent the eggs from curdling. Slowly whisk in the remaining milk.

Pour the milk mixture back into the saucepan and cook over low heat, stirring constantly with a rubber spatula, until slightly thickened, 2 to 5 minutes. (Do not let the custard boil.) The custard is ready when your finger leaves a clean path when you run it across the spatula.

Pour the hot custard through the strainer into the bowl with the chocolate. Let the chocolate melt, undisturbed, for about 1 minute, then stir until the chocolate is completely melted.

Clean the stand mixer bowl with a paper towel. Add the warm chocolate custard and whip on low speed until glossy but still warm to the touch, or between 105º to 115ºF (40º to 45ºC) on a digital thermometer, about 1 minute.

Remove the stand mixer bowl and scrape the chocolate custard off the whisk attachment. Add half of the whipped cream to the stand mixer bowl.

Using a rubber spatula, fold the whipped cream into the chocolate custard until just combined (there should still be streaks of whipped cream). Add the remaining whipped cream and gently fold the cream into the mousse until just combined.

Divide the mousse among eight 1/2-cup (4-ounce | 120-ml) ramekins or small bowls, tap the ramekins lightly on the counter a few times to settle the mousse, and use teh back of a small spoon to smooth the top.

Cover the ramekins with plastic wrap (do not let the plastic wrap touch the mousse) and refrigerate at least 2 hours or up to 3 days.

Line a rimmed baking sheet with a non-stick baking mat or parchment paper.

Using a serrated knife, cut the hazelnuts in half along the seam. (It’s fine if some break into smaller pieces.)

In a medium saucepan, combine the sugar, salt, and 2 tablespoons of water (do not stir). Bring to a boil over medium-high heat and boil, swirling the pan occasionally, just until the sugar begins to caramelize and turn golden brown around the edges of the pan, 4 to 6 minutes.

Immediately add the hazelnuts to the sugar syrup and use a metal spoon or silicone spatula to stir the nuts until they’re well coated in the syrup and just begin to turn light golden brown, 30 to 45 seconds.

Stir in the cocoa butter or coconut oil and continue to stir until the cocoa butter has melted or the nuts are evenly coated with the oil, about 10 seconds, then scrape the hazelnuts onto the prepared baking sheet.

Using two spoons, immediately begin breaking the hot nuts apart. When the nuts are cool enough to handle, use your fingers to separate the nuts.