Toasted hazelnuts will yield a more intense flavor. Please read About Tortes.

Have all ingredients at room temperature, about 70°F. Preheat the oven to 350°F. Grease and flour the bottom of a 10-inch springform pan and line with a round of parchment paper.

Beat in a large bowl, or in a stand mixer with the whisk attachment, at medium-high speed for 1 minute:

Gradually add and beat well until thick and lemon colored:

Fold in, blending well:

Using clean beaters (or clean the whisk attachment, transfer the yolk mixture to another bowl, and clean the mixer bowl), beat in a large bowl at medium-high speed until stiff but not dry:

Fold one-quarter of the egg whites into the batter, then fold in the remaining whites. Scrape the batter into the pan. Bake until a toothpick inserted into the center comes out clean, about 40 minutes.

Let cool in the pan on a rack; the center will sink. To level and unmold, see About Tortes.

Serve with:

or spread the cake with: