Preheat oven to 180ºC/160ºC fan/Gas 4.
Line a Swiss roll pan with baking paper and lightly spray it with vegetable oil.
Use an electric whisk to whisk egg whites with a pinch of salt until they form soft peaks and hold their shape.
Gradually whisk in caster sugar until stiff and glossy but not dry.
Using a spatula, fold the icing sugar and vinegar into the meringue.
Pour the mixture into a Swiss roll pan and smooth the top with a spatula.
Bake for 10 minutes then turn the temperature down to 120ºC/100ºC fan/Gas 4 and bake for a further 15 minutes.
Lay a sheet of baking paper on a work surface and dust it with icing sugar. Turn the baked meringue out on top of the paper, and leave to cool.
Meanwhile, whisk the double cream until thick and fold through the yoghurt. Adding the yoghurt will loosen the filling slightly. The end result should be the filling is just holding its shape and not too thick.
Reserve 6 tablespoons of cream and yogurt filling then spread the rest over the top of the meringue, leaving a 2cm gap around the edges.
Scatter the chopped strawberries over the top.
Starting at the long edge, roll the meringue tightly using the baking paper to help. The finished roulade will probably crack a little, but don’t worry this all adds to its rustic charm!
Spread the reserved cream and yoghurt filling on top of the roulade and decorate with whole strawberries.