Pistachio Lemon Semifreddo Cake with Toasted Meringue

Preheat your oven to 175°C (350°F). Grease a 20cm springform pan and line the bottom with parchment paper.

In a food processor, pulse the shelled pistachios with 20g of granulated sugar until finely ground but not oily. Transfer to a bowl and whisk in the all-purpose flour, baking powder, and salt.

In a stand mixer fitted with the paddle attachment, cream the room temperature butter and the remaining 80g of sugar on medium-high speed until light, fluffy, and pale in color.

Beat the eggs into the butter mixture one at a time, scraping down the sides of the bowl between additions. Mix in the vanilla extract. Gently fold in the dry pistachio mixture just until no flour streaks remain.

Spread the batter evenly into the prepared springform pan. Bake at 175°C (350°F) for 20 to 25 minutes.

Allow the cake to cool completely in the springform pan. Do not remove the sides, as the pan will act as the mold for the semifreddo.

For the semifreddo, whip the cold heavy cream in a clean bowl until soft peaks form. Do not overwhip. Store the whipped cream in the refrigerator while preparing the lemon base.

Create a double boiler by bringing 2 inches of water to a simmer in a saucepan. In a heatproof bowl set over the simmering water, whisk together the whole eggs, egg yolks, sugar, lemon juice, lemon zest, and salt.

Cook the lemon mixture over the double boiler, whisking constantly, until it reaches 74°C (165°F) on an instant-read thermometer and thickens into a light custard.

Remove the bowl from the heat. Using a stand mixer or hand mixer, whip the hot lemon mixture on medium-high speed until it cools down to room temperature and becomes very pale, thick, and voluminous.

Retrieve the chilled whipped cream. Gently fold it into the cooled lemon mixture in three separate additions using a flexible spatula, preserving as much air as possible.

Pour the semifreddo mixture directly over the cooled pistachio cake inside the springform pan. Smooth the surface evenly.

Wrap the pan tightly in plastic wrap. Freeze for a minimum of 8 hours, or ideally overnight, until completely solid.

Once the cake is fully frozen, prepare the meringue. Whisk the egg whites, sugar, and cream of tartar in a heatproof bowl set over simmering water. Cook while whisking constantly until the sugar dissolves completely and the mixture hits 74°C (165°F).

Transfer the hot egg white mixture to a stand mixer. Whip on high speed until glossy, stiff peaks form and the outside of the mixing bowl feels cool to the touch.

Remove the frozen cake from the springform pan and place it on a serving platter. Generously swoop and swirl the Swiss meringue over the top and sides of the semifreddo using an offset spatula or the back of a spoon.

Using a culinary blowtorch, carefully toast the meringue until the peaks are dark brown and the valleys are golden. Allow the cake to rest at room temperature for 10 minutes before slicing to soften the semifreddo slightly.