Beat the sugar, egg yolks and water using the whisk on a hand mixer until the mixture is light and fluffy. Beat the egg whites with the salt until stiff. Gradually add the sugar and continue beating until the egg whites turns glossy. Sieve the flour, add to the mixture in layers along with the egg whites and carefully fold in using a rubber spatula. Spread the sponge mixture into a rectangle (approx. 1 cm thick) on a baking tray lined with baking paper.
Approx. 6 mins. in the centre of an oven preheated to 220°C. Remove the sponge, tip the cake and paper out onto a fresh sheet of baking paper, wipe the upper layer of paper with a damp towel and peel away carefully. Cover the sponge immediately with the upturned tray, leave to cool.
Beat the cream and sugar until stiff, set aside one third. Mix the strawberries into the remainder of the whipped cream.
Spread the strawberry cream over the sponge, leaving a border of approx. 2 cm all round. Roll up tightly from the narrow end. Spread the reserved cream over the roulade, sprinkle with chocolate shavings.