Preheat the oven to 180°C. In a medium bowl, mix all dry ingredients. In a separate bowl, whisk the egg whites to soft peaks. Set aside.
In a large bowl, whisk egg yolks with an electric mixer. Add sugar gradually, by spoonfuls and beat well after each addition. Mix the egg white mixture into the egg yolk mixture alternately with the dry ingredients and fold gently.
Pour the batter evenly into the prepared rectangle baking pan, lined with baking paper. Bake for around 12 minutes until done.
Meanwhile, dash another baking paper with sifted white or icing sugar. Turn the pan into the sugared baking paper and carefully remove the pan then remove the paper gently from the cake.
Spread the margarine evenly over the cake, dash with sugar over the margarine. Roll the cake with the longest side facing you.
Cover the cake with baking paper and refrigerate for 2-3 hours. Slice gently, serve and enjoy.
