Add a piece of parchment paper over a baking pan.
Spread the batter evenly onto the prepared baking pan and bake for 13 minutes, until the top springs back when touched.
Remove the pan from the oven and let cool for a minute. Put a kitchen towel to the side and lift up the parchment paper and flip on its other side onto the kitchen towel. The parchment paper side should now be side up.
Carefully peel away the parchment paper from the sponge cake. Place the parchment paper over again and gently roll up inside the kitchen towel while still warm. We want the cake to cool down in its rolled up form to prevent cracking.
Set aside until completely cooled.