Tiger Skin Chiffon Cake Roll

Preheat the oven to 350 degrees F (175 degrees C). Line a sheet cake pan with parchment paper. (5 minutes)

In a bowl, beat 4 egg yolks and 2 tablespoons of sugar until the mixture is pale yellow and thick. Gradually add corn oil, 1 tablespoon at a time, mixing well after each addition. Stir in milk until well combined. Sift together 1/2 cup plus 2 tablespoons of flour and baking powder. Gently fold the dry ingredients into the egg yolk mixture until just combined. (10 minutes)

In a clean, grease-free glass, metal, or ceramic bowl, beat the egg whites until foamy. Gradually add the remaining 4 tablespoons of sugar, continuing to beat until stiff, glossy peaks form. Gently fold 1/3 of the egg white mixture into the egg yolk batter to lighten it. Then, pour the egg yolk batter into the bowl with the remaining egg white mixture and gently fold until just combined, being careful not to deflate the egg whites. Transfer the batter onto the prepared sheet cake pan and spread evenly. (15 minutes)

Bake in the preheated oven until the top is golden brown and the cake springs back lightly when touched, about 15 to 20 minutes. (20 minutes)

Remove the cake from the oven and let it cool until safe to handle, about 30 minutes. Dust the top of the cake generously with confectioners' sugar. Flip the cake over onto another piece of parchment paper. Carefully peel off the parchment paper that was on the bottom of the cake. (35 minutes)

Spread an even layer of chocolate frosting onto the cooled sheet cake. Gently roll the cake into a log shape, using the parchment paper to help guide you. Wrap the cake roll tightly in parchment paper and refrigerate for at least 1 hour to allow the frosting to set and the cake to firm up. (65 minutes)

Increase the oven heat to 400 degrees F (200 degrees C). Line an 8-inch cake pan with aluminum foil or parchment paper, ensuring it extends slightly over the edges for easy removal. (5 minutes)

In a bowl, combine 3 egg yolks, 3 tablespoons of sugar, cornstarch, and vanilla extract. Beat with an electric mixer until the batter is pale yellow and thick – this step is crucial for achieving the desired tiger skin effect. (10 minutes)

Pour the batter into the prepared pan and spread it evenly to create a thin layer. (2 minutes)

Bake in the preheated oven, keeping a close eye on the color change, for 5 to 10 minutes. The tiger skin should be removed immediately when the desired golden-brown, mottled color is achieved. Overbaking will result in a dry, brittle skin. Allow the tiger skin to cool completely, about 30 minutes. (35 minutes)

Flip the tiger skin over and carefully remove the parchment paper from the bottom. (5 minutes)

Spread an even layer of vanilla frosting onto the tiger skin. Carefully unwrap the refrigerated cake roll and remove the remaining parchment paper. Wrap the cake roll with the tiger skin, gently pressing it to adhere. (10 minutes)

Place the assembled cake roll on a serving platter. Slice and serve chilled. Enjoy! (5 minutes)