Making swiss roll looks difficult but it is as simple as making a sponge cake.
Preheat oven to fan 180┬░C and cover a 33cm x 23cm flat baking pan with baking parchment. Take 2 bowls and separate the egg white and egg yolks. Add the sugar, cocoa powder and a peck of salt to egg yolks and stir well getting a foamy mixture.
Sift the flour into a small bowl and set aside. Whisk the eggs white with a blender and add to the egg youlk mixture. Using a large wood spoon, gradually and gently fold the flour into the mixture, until evenly mixed. Stir always only one direction!
Gently pour the mixture into the tin and lightly level the surface. Bake for 8-10 minutes until well risen, golden and firm to the touch.
Whilst the Swiss roll is baking place a large kitchen cloth onto the work surface. As soon as the cake is baked turn out onto the cloth, let the parchment the Swiss roll was cooked in. Tightly wind with the cloth and set aside for 10-15 minutes, let it cool down. During this time the cake will adapt the roll form. After this time remove the parchment and spread quickly with orange cream.
While the sponge cake cool down prepare the orange cream. Bring to the boil on medium heat the orange juice, add the pudding powder according to the wrapping instruction, add the sugar as well and cook a well firmed cream. Remove from heat and mix into the butter, it will melted and soft while the pudding is warm. Cool down the orange cream to room temperature and fill into the swiss roll.
Roll up from a short end, using the cloth and removed parchment to help. Leave to cool in the parchment to maintain roll shape. Before serving transfer to tray and sprinkle with icing sugar. Then slice as required, preferable oval.