Method

• 1.
  For the pastry, place flour and a pinch of salt in a bowl. Using your fingers, rub in butter until it resembles coarse crumbs. Add egg yolk and thyme. Combine vinegar and 1/4 cup (60ml) water in a jug with 4 ice cubes. Drain, then fold into flour mixture until it forms a shaggy dough. Enclose in plastic wrap and chill for 2 hours.
• 2.
  Preheat oven to 200°C.
• 3.
  Roll out pastry on a lightly floured work surface to 3mm thick and use to line a 24cm fluted ceramic dish, trimming excess. Line with baking paper and fill with pastry weights. Bake for 25 minutes or until light golden. Remove weights and paper, and bake for a further 20 minutes or until base is cooked.
• 4.
  Reduce oven to 160°C.
• 5.
  Heat oil in a frypan over low heat. Add onion and 1/2 tsp salt. Cook, stirring, for 12 minutes or until caramelised. Cool. Add to pastry case with half rosemary leaves and 100g feta.
• 6.
  Whisk egg, milk and paprika in a bowl. Season and pour into pastry case. Coat sweet potato with maple and arrange over filling. Scatter with remaining 50g feta and rosemary.
• 7.
  Bake for 1 hour or until just set. Cool slightly, then serve.