3 eggs, separated185 gm caster sugar110 gm (¾ cup) self-raising flour1 tbsp golden syrup, combined with 1 tbsp boiling water200 gm strawberry, raspberry or plum jam
Using an electric mixer, whisk eggwhites until soft peaks form, then gradually add 110gm (½ cup) sugar and whisk until firm peaks form and mixture is stiff and glossy. Add egg yolks one at a time, whisking until just combined.
Sift flour and ½ tsp salt into a bowl, then repeat twice more. Add golden syrup mixture and sifted flour to egg mixture and, using a large metal spoon, gently fold in until just combined. Spoon mixture into a baking paper-lined 26x32cm Swiss roll tin, gently smooth top, then bake at 180C for 12 minutes or until top springs back when pressed.
Scatter remaining sugar 1cm from end of a clean tea towel to cover an area the same size as cake tin, then carefully invert cake over sugar and peel away base paper. Using a serrated knife, trim short ends of hot cake, then, using towel as a guide, roll up from a short side and leave to cool, wrapped in the towel.
Carefully unroll cake, spread with jam leaving a 1cm border, then re-roll and place, seam-side down, on a plate. Serve cake cut into slices. Jam roll will keep in an airtight container for up to 2 days.