Preheat the oven to 180oC/Gas Mark 4.
Put the hazelnuts on a small baking tray and roast for 8 minutes or until golden; set aside to cool.
Meanwhile, grease and line the base and sides of 2 loose-bottomed 18cm (8IN) sandwich cake tins.
Put the cooled hazelnuts and 1 tbsp caster sugar in a small food processor; pulse until ground (a few chunky pieces are fine).
Put the egg whites and pinch of salt in a mixing bowl. Using electric beaters, whisk to stiff peaks, then whisk in 150g (51⁄2oz) caster sugar in 3 additions.
Fold through the ground hazelnuts and vinegar, divide between the tins, smoothing the tops, then bake for 30-35 minutes. Set aside to cool.
Using electric beaters, whisk the cream, remaining sugar and vanilla to soft peaks. Stir in the yoghurt.
Remove the meringue cakes from the tins; place one on a cake stand. Spread with half the cream mixture and tumble over half the strawberries.
Repeat with a second layer and serve at once.