These are great dinner-party desserts that can be knocked up well in advance and assembled at the last minute. They look very impressive, thanks to the bulky-yet-light meringue. If you know where to buy good, ready-made meringues, you can cheat; when making your own, the secret is to get them slightly gooey in the middle.
For the meringue
3 egg whites
100g caster sugar
1tsp white wine vinegar
For the apple purée
1 large bramley or cooking apple, peeled, cored and roughly chopped
2tbsp caster sugar
100ml whipped cream
Preheat the oven to 120C/gas mark 1. In a mixing machine with a whisk attachment, or by hand (though this will take quite a while), whisk the egg whites until stiff. Add the caster sugar and continue whisking until the mixture is really stiff and shiny.
Add the cornflour and vinegar and whisk again for about 30 seconds. On a clean baking tray lined with either silicone or greaseproof paper, spoon the mixture on in the shape of 4 round domes, making an indentation with the back of the spoon in the middle of each. Alternatively, you can also just make one big meringue.
Cook in the oven for 1 hours so the meringue is crisp on the outside and soft in the middle, but don't let the outside colour – you want it nice and white. You may need to cook it a little longer, depending on your oven. Remove from the oven and leave to cool.
Meanwhile, put the apple in a saucepan with the sugar and cook on a medium heat for 5-10 minutes, stirring as it's cooking until it's almost a purée. Put to one side and leave to cool. Blend half of the blackberries in a liquidiser until smooth, then strain through a fine-meshed sieve.
To serve, fold the whipped cream into the apple purée and spoon this mixture into the cavity of the meringue. Scatter over the blackberries and spoon the sauce around and over.