Hurricane Swiss Roll with Strawberry jam ~ 飓风蛋糕卷

I had always wanted to make a Swiss Roll but have been procrastinating for a long time as I doubt whether I can master the art of rolling the cake.  After seeing so many pretty Hurricane Swiss Roll posts on Facebook  and blogs, the temptation was too great to resist.  So here's my first attempt at a roll cake.

Hurricane Swiss Roll with Strawberry jam ~  飓风蛋糕卷
 (adapted from 'here' .  Please visit this site for illustrated pictures on how to achieve the 'Hurricane' pattern)
Ingredients (A)

• 4 egg yolks
• 60 gm caster sugar
• 30 ml milk
• 30 ml canola oil
• 1 tsp vanilla
• 70 gm plain flour, sifted
• 1 Tbsp cocoa powder
• Strawberry jam or any other jam of your choice

(B)  4 egg whites, 50 gm caster sugar

Method

1. Line a 10" x 10" square pan with parchment paper, set aside.
2. In a bowl, mix egg yolks, sugar, milk, oil, vanilla with a ball whisk.  Mix well and add in sifted flour.  Mix till well incorporated.
3. Divide into 2 portions.  Add one portion with sifted cocoa powder, mix well.  Leave the other portion as it is.
4. In a clean mixing bowl, beat the egg whites till foamy and gradually add in the sugar in 3 batches.  Beat till stiff peaks form.
5. Fold 1/2 the meringue into the cocoa mixture, mix well.  Fold the other 1/2 into the plain mixture, mix well. but do not overmix as the egg whites may deflate.
6. Pour the plain mixture into the pan and use a spatula to spread the mixture into the corners of the pan.  Level the surface.
7. Gently pour the cocoa mixture over the plain mixture and use a spatula to spread it out evenly.
8. Then using the end of a spatula or ladle, draw lines vertically up and down, then horizontally to and fro without lifting the spatula or ladle)
9. Tap the pan a few times to expel any air bubbles.
10. Bake in a preheated oven @ 180 deg.C for 20 mins. till golden brown and tap your finger on the surface of the cake to check for firmness and if it springs back, the cake is done.
11. Remove the cake from the oven and put on a wire rack.  Open up the parchment paper.  Then place a clean sheet of parchment paper over the cake and with a hard surface for backing, flip the cake over, chocolate side down.  Remove the parchment paper.  Let cake cool.
12. Spread strawberry jam onto the cake leaving 1/2 inch from the top and sides of the cake.   Then slowly roll up the cake, aided by the parchment paper.   Wrap the cake up with parchment paper, place it in a plastic  bag and let chill in the fridge for a few hours or overnight.
13. Slice to serve.