Frozen Chocolate and Hazelnut Praline Cream (Semifreddo Al Croccante)

PralinePreheat the oven to 300˚F.

Rub a thin film of flavorless oil onto a rimmed baking sheet. Place the hazelnuts on another rimmed baking sheet and keep them warm in the preheated oven while you caramelize the sugar.

Have a candy thermometer ready near the stove. In a large, heavy saucepan over medium-low heat, stir together the sugar, water, butter, lemon juice and salt. Keep stirring with a wooden spoon until all the sugar is dissolved but the mixture isn’t yet boiling. Remove the spoon. Then turn up the heat to medium-high and boil, swirling the pan every now and then so the syrup cooks evenly.

After about 10 minutes, the syrup will begin to turn brown and thicken. Now resume stirring with your wooden spoon until the mixture reaches 300˚F on the candy thermometer. Take the warm hazelnuts out of the oven and add them to the pan. Stir for a minute to coat them in the caramel, then carefully turn the praline out onto the prepared baking sheet in a thin layer. Let cool completely.

The praline can be made up to a few days ahead of time. Just wrap it airtight and store it at cool room temperature.

ZabaglioneSet a heatproof bowl over a saucepan of simmering water. Add the yolks and liqueur to the bowl and whisk together. Keep whisking continuously for 6 to 8 minutes, until the mixture has thickened and holds its shape. Take the bowl off the heat and let the mixture cool to room temperature; then cover the bowl and chill the zabaglione until it’s completely cold, at least 2 hours. Keep in the fridge until you’re ready to make the semifreddo, no more than 8 hours or it will begin to lose volume.

SemifreddoLine a 9- by 5-inch loaf pan with plastic wrap that extends beyond the edges of the pan; set aside. In a small saucepan over medium heat, bring 1/2 cup of the cream just to a boil. Remove the pan from the heat, add the chocolate, and whisk until the chocolate is melted, then whisk in another 1/2 cup of the cream. Chill this chocolate cream until completely cold, at least 30 minutes.

Meanwhile, break up the praline into shards; save a few for garnish, wrapped airtight. Pulse the rest in a food processor until ground to the texture of uncooked rice (or seal it in a strong plastic or silicone bag and smash it with a hammer).

In a large bowl, combine the remaining 2/3 cup (160 ml) of heavy cream, the chocolate cream, and the vanilla extract. Whip with an electric mixer until the mixture is billowy and holds its shape. By hand, gently fold in the zabaglione, then the praline. Scrape the mixture into the prepared loaf pan, cover tightly, and freeze for a good 12 hours. When you’re ready, turn the semifreddo out of the loaf pan onto a serving plate and garnish with the reserved praline shards. Slice crosswise into 1 1/2 inch servings.