In an electric mixer bowl, stir
together with yeast and milk.
Leave for about 15 minutes. Stir in
the sugar, salt and about 150 g of the flour.
Using a dough hook, slowly add the
remaining flour. Beat on a high speed until the dough pulls away from
the sides of the bowl. Cover and leave to rise in a warm place until
doubled in size, about 11/2 hours. Knead until smooth, wrap
in greaseproof paper and chill for 15 minutes.
Roll out the butter between the two
sheets of greaseproof paper to make two 15 x 10cm rectangles.
Roll out the dough to 30 x 20cm.
Interleave the butter with the dough. With a short side facing you, roll
it out again to 30 x 20cm.
Fold in thirds again, wrap and chill
for 30 minutes. Repeat procedure twice, then chill for 2 hours.
Roll out the dough to a rectangle
about 3mm thick. Trim the sides. Cut into 18 equal-size triangles.
Roll up from base to point. Place
point down on baking sheets and form crescents. Cover and leave to rise
in a warm place until more than doubled in size, about 1 - 11/2
hours.
Preheat the oven to 240oC/475oF/Gas 9.
Brush with egg.
Bake for 2 minutes. Lower the heat to
190oC/375oF/Gas 5 and bake until golden, about
10-12 minutes. Serve warm.