METHOD

1. Preheat oven to 180°C (350°F). To make the pastry, place the flour, baking powder and sugar in a food processor and process to combine. Add the butter and process until the mixture resembles fine breadcrumbs. While the motor is running, gradually add the water and vanilla and process until the mixture comes together to form a smooth dough. Flatten into a disc, cover with plastic wrap and place in the fridge for 30 minutes. Roll the pastry out between 2 sheets of non-stick baking paper to a 5mm-thick rough 30cm x 42cm rectangle. Refrigerate for 10–15 minutes or until firm. Place the dough on a 30cm x 42cm baking tray and remove the top sheet of non-stick baking paper. 
2. Mix to combine the almond meal and caster sugar and sprinkle over the dough, leaving a 4cm border. 
3. Place white sugar and vanilla seeds in a bowl and rub with your fingertips to combine. Add the peach and toss to combine. 
4. Layer the almond meal mixture with the peach wedges, alternating colours, and fold the edges of the pastry around the peaches. Brush the edges with eggwhite and sprinkle with the extra white sugar. Bake for 40–45 minutes or until the pastry is cooked through and golden. Dust with icing sugar to serve. Serves 6–8.