Preheat the oven to 200C
Line an oven tray with baking parchment and sprinkle the caster sugar over it evenly.
Whisk the sugar and the eggs for at least 10 minutes until really pale and visibly thickened. You should get a trail when the whisk has been removed from the mixture.
Add in the vanilla extract.
Fold in the flour very gently and slowly.
Spread evenly over the sugar sprinkled baking parchment and put in the oven to cook for 11 minutes. This was the biggest revelation for me, that the cake cooks in such a short time - If you get a move on, you could even have one ready for your afters (dessert if you are not northern ;-))
Remove from the oven and allow to cool slightly.
Before the cake is fully cooled, roll it so the cake is still malleable enough to shape - I also cut off the very ends to give a neat finish but I think that was a bit pretentious and actually wasted valuable cake.
Allow to cool completely.
Spread a generous layer of the jam and cream on the cake (Spread thin slices of strawberries evenly over the cake if you are adding fresh fruit.)
Roll up again, sprinkle with the icing sugar and put on a rectangle plate if you have one.