150ml egg white (from about 4 eggs), at room temperature
200g caster sugar
1tsp white vinegar
300g blackberries (or other berries)
1½ tbsp icing sugar
250g low-fat Greek yoghurt
Tiny mint leaves, for garnishing
Preheat the oven to 150C/gas mark 2 and line two large baking trays with baking paper.
Place the egg white in the bowl of an electric mixer and beat until soft peaks form. Add the caster sugar a tablespoonful at a time until incorporated. Keep whisking for one to two minutes, or until stiff, glossy peaks form.
Sift the cornflour over the top, add the vinegar and gently fold through the mixture. Place 16 dollops of meringue, about 7.5-10cm in size, leaving plenty of space in between.
Reduce the oven to 120C/Gas mark ½ and bake for 35 minutes.
Turn off the oven and allow the meringues to cool for a couple of hours. Gently crush the berries in a bowl with the back of a fork and mix in the icing sugar until dissolved.
Serve the meringues with the berries and yoghurt, garnished with the mint.