8 egg yolks + 4 egg whites, divided (save remaining 4 egg whites for another use)
3/4 cups + 2 tablespoons sugar (175 grams)
1 stick + 2 tablespoons unsalted butter
1 teaspoon kosher salt
1 cup heavy cream
Chocolate wafers, for serving (optional)
Jam, for serving (optional)
Melt butter, then set aside to cool to room temperature. Cream egg yolks and sugar until they become light, creamy, and fluffy. While mixing, drizzle cooled butter into sugar-egg yolk mixture.
Fold salt into sugar-egg yolk mixture. Whisk heavy cream to medium-to-stiff peaks and fold into sugar-egg yolk mixture.
Whisk egg whites to peaks and fold into semifreddo mixture.
Pour into a container, cover tightly, and freeze for several hours or overnight to set.
Serve in scoops, topped with crumbled chocolate wafers and jam, if desired.
This semifreddo will keep for two to three days tightly sealed in the freezer — after this it will start to break down.