Preheat oven to 375° F. Lightly grease a half sheet pan (18 x 13); line with parchment paper. Grease and flour parchment paper as well.
Place the egg whites in the bowl of a stand mixer, fitted with a whisk attachment. Whisk over high speed until light and foamy. Slowly sprinkle in ½ cup granulated sugar and continue whisking over medium-high speed until the egg whites have reached medium peaks. Transfer to a large clean bowl.
Using the same bowl of the stand mixer used for the egg whites (washed and dried well), add egg yolks, remaining ½ cup granulated sugar, and vanilla. Beat 4-5 minutes until mixture is pale yellow and creamy. Slowly add the egg white mixture to the egg yolk mixture (in stages); gently folding in between until fully combined.
Add the sifted cake flour to the batter, and fold in gently with a spatula. Repeat until all of the flour has been incorporated and the mixture is smooth and fluffy. Transfer the batter onto the prepared sheet pan and spread into an even layer. Bake the cake for 10 minutes, the cake should spring back when gently pressed in the center. Let the cake cool for 2 minutes.
Meanwhile, place a clean thin kitchen towel linen on countertop and dust with confectioner’s sugar. Quickly turn the pan onto the sugar-dusted towel and carefully peel off paper. Roll up cake and towel together, starting with narrow end. Let cool completely (seam side down on wire rack, about 45 minutes).
Unroll the cake so that it lays completely flat. Using an offset spatula, spread the preserves into a very thin layer on the cake. Carefully re-roll the cake (without the towel), narrow end to narrow end, into a spiral. Place the cake seam-side down on a long serving platter, cover tightly with plastic wrap, and refrigerate for at least one to two hours.
Just before serving, dust the cake with confectioner’s sugar and top with fresh strawberries. Slice into rounds and serve immediately. Serve with whipped cream on the side (optional). Enjoy!
