Raspberry Swiss roll

Preheat the oven to 200 &degC.
Grease a 23 x 33 cm Swiss roll cake tin and line with baking paper. Grease once more.
Using an electric beater, whisk together the eggs and castor sugar until thick and pale yellow and the mixture falls back into the bowl forming a ribbon when a little is lifted in the beaters ? about 15 minutes.
Sift the cake flour on top and fold in with a metal spoon.
Fold in 15 ml warm water.Bake for 10 to 12 minutes or until the cake is springy to the touch.
Sprinkle a damp tea towel with castor sugar.
Meanwhile, heat the jam.
Turn the cake out onto the tea towel as soon as it comes out of the oven.
Remove the baking paper and neaten the edges.
Spread the heated jam over the cake and roll up from one short end, working rapidly and using the tea towel to help you.
Cool the cake on a wire rack.