Tiramisu Yule Log - PCOS-Friendly Recipe

Heat oven to 350 °F with rack in middle. Butter pan and line bottom and sides with 1 sheet of parchment paper. Butter paper and dust with additional flour, knocking out excess.

Beat together yolks, vanilla, and 1/2 cup sugar in a large bowl with an electric mixer at high speed until thick and pale and mixture forms a ribbon that takes 2 seconds to dissolve when beaters are lifted, 5 to 8 minutes in a stand mixer or 8 to 12 minutes with a handheld. Sift half of flour over yolks and fold it in gently but thoroughly, then sift and fold in remaining flour.

Beat whites with salt and cream of tartar in a large metal bowl with cleaned beaters at medium speed until they just hold soft peaks. Beat in remaining 2 tablespoons sugar, 1/2 tablespoon at a time, and continue to beat until whites just hold stiff peaks.

Fold 1/4 of whites into yolk mixture to lighten, then fold in remaining whites gently but thoroughly.

Stir 1/2 cup batter into melted butter in a small bowl until combined, then fold butter mixture into batter gently but thoroughly. Spread batter evenly in sheet pan and rap once on counter to help eliminate air bubbles.

Bake until top of cake springs back when gently pressed with finger, 7 to 10 minutes.

Sift top of hot cake evenly with confectioners' sugar and cover cake with a clean kitchen towel (not terry cloth) followed by a baking sheet. Holding sheet and cake pan together with oven mitts, flip cake onto cloth on baking sheet. Carefully peel off and discard parchment paper.

With a long side nearest you and using towel as an aid, roll up cake in towel, jelly-roll style, keeping it wrapped in towel. Cool cake completely, seam-side down in towel, on a rack.