Make flaky pastry. Sift flours and salt into a large bowl; coarsely grate over frozen butter. Using fingertips, rub butter into flour to separate strands. Gradually add ²⁄³ cup (160ml) chilled water, mixing with a flat-bladed knife until mixture just comes together. Transfer dough to a lightly gluten-free floured surface and shape into a flat disc. Enclose in plastic wrap; refrigerate for 1 hour before using.

Preheat oven to 220°C/425°F. Line a large oven tray with baking paper.

Cut out the centre vein from lime leaves then slice leaves as finely as possible. Reserve 1 sliced leaf for dipping sauce. Process remaining sliced leaves with chicken, curry paste, green onion, coriander leaves and stems, breadcrumbs and fish sauce until well combined. Transfer to a large bowl.

Cut pastry into half. Roll halves out between two sheets of baking paper to 3mm (¹⁄8in) thick and 27cm (10¾in) square. Cut each sheet of pastry in half to form four large rectangles of pastry 13.5cm x 27cm (5½in x 10¾in). Divide the chicken mixture into four and spread along one edge of each pastry rectangle. Lightly brush edge with combined egg yolk and 1 tablespoon chilled water; roll up to enclose, pressing edges to seal. Cut eight diagonal slashes crossways along each sausage roll. Brush with egg yolk mixture; sprinkle with sesame seeds.

Place sausage rolls on lined tray; bake for 30 minutes or until browned and chicken is cooked through.

Meanwhile, to make the dipping sauce, combine reserved lime leaf, the chilli sauce and lime juice in a small bowl.

Cut sausage rolls on the diagonal; serve warm or room temperature with the dipping sauce.