Nutella Swiss Roll

Credits: Stephanie Jaworski, Joyofbaking.com

Sponge Cake: 

4 large eggs

1 large (20 grams) egg yolk

1/3 cup (35 grams) sifted cake flour

3 tablespoons (30 grams) cornstarch (corn flour)

1/2 cup (100 grams) plus 1 tablespoon (15 grams) granulated white sugar (divided)

1 teaspoon pure vanilla extract

1/4 teaspoon cream of tartar

Filling:
Nutella (amount as desired)

For Sponge Cake: 

1. Preheat oven to 450 degrees F (230 degrees C) and place oven rack in the center of the oven. Butter, or spray with a nonstick vegetable spray, a 17x12 inch (43x30 cm) baking pan, line it with parchment paper, and then butter and flour the paper (or spray with a nonstick vegetable/flour spray).
2. While the eggs are still cold separate two of the eggs, placing the yolks in one bowl and the whites in another bowl. To the yolks, add the additional yolk, and the two remaining eggs. Meanwhile, in a small bowl whisk the flour with the cornstarch.
3. Place the egg yolks and whole eggs, along with 1/2 cup (100 grams) of the sugar, in your electric mixer, fitted with the paddle attachment. Beat on high speed for five minutes, or until thick, pale yellow, and fluffy. (When you slowly raise the beaters the batter will fall back into the bowl in slow ribbons.) Then beat in the vanilla extract. Sift half the flour mixture over the beaten egg mixture and fold in gently with a rubber spatula, just until the flour is incorporated. Sift the remaining flour mixture into the batter and fold in. 
4. In a clean bowl, with the whisk attachment, beat the egg whites until foamy. Add the cream of tartar and continue beating until soft peaks form. Sprinkle in the remaining one tablespoon sugar and beat until stiff peaks form. Gently fold a little of the whites into the batter to lighten it, and then add the rest of the whites.
5. Pour the batter into prepared pan, spreading evenly with an offset spatula or spoon. Bake for about 8-10 minutes or until golden brown and when lightly pressed, springs back. Immediately upon removing the cake from the oven sprinkle with confectioners sugar and then invert the cake onto a clean dish towel. Remove the parchment paper, sprinkle with confectioners sugar, and roll up the sponge, with the towel. Place on a wire rack to cool for 10-15mins.

Assemble:

1. Place a piece of parchment paper on counter table.  Sprinkle icing sugar on parchment paper.  Remove towel and unroll the sponge cake.  Warm nutella in a microwave for 30secs to make it spreadable.  Spread nutella onto sponge cake leaving 1cm circumference empty.
   (Note: When you roll, the nutella will compress and fill up the empty space.)
2. Roll the sponge cake tightly using parchment paper to press as you roll.  *Similar movement to rolling sushi*
3. Wrap rolled cake in parchment paper and twist both ends leaving cake to cool completely.

Serves 6-8 people.