Swiss roll

Method

1. Grease a 30 × 25 cm Swiss roll tin and line with greased baking paper, or make a paper case this size using thick baking paper.
2. Sift flour with salt. Place the eggs and sugar in a heatproof bowl and stand over a pan of gently simmering water, not boiling. Whisk together for about 10 minutes or until mixture is very thick and creamy. If using an electric mixer, whisking over hot water is not necessary.
3. Remove bowl from water and continue whisking mixture until cool. Fold in flour as lightly as possible with a metal spoon. Lastly, fold in hot water. Pour into prepared tin, shake into corners and spread evenly using a metal spatula. Bake in a preheated hot oven (220°C) for 7–12 minutes or until pale golden and springy. Do not overcook as it makes rolling up difficult.
4. Quickly turn out the sponge onto a dish towel well sprinkled with caster sugar. Carefully strip off lining paper. Trim off crisp edges with a sharp knife. Roll in towel and cool.
5. Unroll sponge. Place jar of jam or curd in saucepan of hot water and when warm spread jam or curd over sponge, taking it almost to the edges. Lifting edges of sugared dish towel nearest you, roll sponge into a neat firm roll.
6. Stand roll on a wire rack with join underneath. Leave until cold, away from any draughts. Sprinkle with a little more caster sugar before serving.