Preheat the oven to 180C. Cover a swiss roll tray with baking paper. Sift the flour, cornflour and baking powder and set aside. Weigh out the sugar, then whisk the egg whites until stiff before gradually whisking in 4 tbsp of the caster sugar.
Whisk the egg yolks with the lemon zest and remaining sugar until they hold a trail, then beat in the lemon juice. Quickly fold in the egg whites with a metal spoon, followed by the flour. Pour into the tray and spread evenly. Bake for 15 minutes or until golden and springy.
Sprinkle a large sheet of grease proof paper with caster sugar and flip the hot swiss roll onto it. Cover with grease proof paper and gently roll up.
Leave to cool.
Once cold, unwind the roll and spread with lemon curd, followed by cream. Finally cover with sliced strawberries and reroll.