Make the dough: combine flour, yeast, salt, sugar, milk and butter. Knead for 5 minutes until smooth. Shape into a rectangle, wrap and refrigerate for 1 hour.

Make the butter block: beat the cold butter between two sheets of baking paper into a 20 cm square. Refrigerate until firm but pliable.

Roll the chilled dough into a rectangle twice the size of the butter block. Place the butter block in the centre and fold the dough over to enclose it completely.

Roll out into a long rectangle. Fold into thirds (letter fold). Wrap and refrigerate for 30 minutes. Repeat the rolling and folding 2 more times, chilling between each fold.

Roll the final dough to 4 mm thick. Cut into long triangles. Roll each triangle from the wide end to the point. Curve the ends inward to form a crescent.

Place on baking trays, brush with egg wash and prove for 2 hours until puffed.

Brush again with egg wash. Bake at 200°C (400°F) for 15–18 minutes until deeply golden.