Pain au Chocolat with Dark Chocolate

Make the dough. In a large bowl stir the water or milk sugar 240 g of the flour the yeast salt and softened butter until they are roughly mixed tip in the rest of the flour and then stir until the dough comes away from the sides turn it out and knead only until it just starts to look smooth do not work it heavily because it still has a long rise ahead.

First rise, then an overnight chill. Put then the dough in a lightly greased bowl cover and leave it at room temperature until it looks puffy about 1 hour then refrigerate the then covered bowl for 8 to 16 hours overnight is ideal.

Pound the butter into a square. Just before you take the dough out of the fridge cut the 340 g cold butter into pieces lay them on a floured sheet of baking paper flour the top and cover with another sheet pound and roll the butter until it is pliable and forms a square about 15 cm across still cold but bendy.

Lock the butter in. Roll the chilled dough on a lightly floured surface into a 30 cm square set the butter square in the centre on the diagonal like a diamond and fold the four flaps of dough over it pinching the seams so the butter is enclosed.

Letter fold, then book fold. Roll the packet into a 25 50 cm rectangle fold one short third into the centre then the opposite third over it a letter fold turn the dough 90 and after that roll it again to 25 50 cm fold both short ends in until they meet in the middle without overlapping then fold the dough in half like a book and turn it 90 wrap and refrigerate for at least 8 hours and up to 24.

Cut, fill and prove. Cut the dough in half and keep one half cold roll the other into a generous 20 60 cm rectangle and cut it into eight 10 15 cm pieces lay one or two chocolate batons at one end of each piece roll it up into a tube and sit it seam side down on a lined tray then press the top gently to flatten it into a rectangle repeat with the second half cover and leave in a warm place until the rolls look light and puffy about 1 hour.

Glaze and bake. Towards the end of the rise, heat the oven to 220°C. Brush the tops with the beaten egg and bake for 18 to 20 minutes, until they are a deep gold. Leave them to cool a little before eating so the structure can set and the chocolate is not molten-hot.