Preheat oven to 170°C fan. Grease and line a 30 x 20cm baking tin with baking parchment (cut the paper higher than the sides of the tin – so the meringue doesn’t catch when it rises).

Put the egg whites and salt into a large mixing bowl and use an electric whisk to whisk to soft peaks.

Gradually add the sugar in spoonfuls, continuing to whisk on a high speed for at least six minutes, until the mixture is glossy and forms stiff peaks.

Using a spatula, spread the mixture into the lined tin and bake for 15 minutes, then reduce the heat to 160°C and bake for another five minutes) until the surface is lightly golden and firm (don’t overcook or it will crack). Remove from the oven and leave to cool completely.

For the mixed berry coulis, make a sugar syrup by placing the sugar and water into a small pan over a medium heat until dissolved, bring to the boil and simmer without stirring for two minutes until syrupy. Pour the sugar syrup over the berries in a bowl and blitz with a handheld soup blender to a purée (pass through a sieve to remove seeds). Add a squeeze of lemon juice if too sweet.

To assemble, place a sheet of baking paper wider than the roulade onto a flat surface and dust with icing sugar. Invert the baked meringue on to the dusted sheet, remove the tin and carefully peel back the lining paper. Spread whipped cream over the surface of the roulade and scatter most of the berries over (reserve some for decoration). With the long edge in front of you, roll the roulade upwards and away from you using the paper to help roll over like a swiss roll. Dust with icing sugar and decorate prettily with berries, and keep chilled.

Serve sliced with the coulis.

Variation: Once you can make and roll a basic roulade, vary the flavours of the meringue mixture by folding in ground almonds, pistachios, cocoa powder or even cinnamon. Fresh kiwis, mango, passion fruit pulp, pomegranates and redcurrants add exotic tastes and vibrant colour.