Christmas leftovers galette

Make the béchamel by melting the butter in a pan and, once foaming, add the flour and cook, stirring, for 2-3 minutes until darkened slightly and smelling toasty. Add the milk slowly, stirring well between each addition, until you have a thick, smooth sauce. Bubble for 2-3 minutes, then stir in the cheeses and season – it should become a very thick sauce. Tip into a bowl, cover the surface with baking paper and leave to cool.

Heat the oven to 190C/fan 170C/gas 5 and line a large baking tray with baking paper. Unravel the pastry onto a lightly floured worksurface and lightly roll to make a square, then cut into a 30cm circle and transfer to the baking sheet. Use scissors to make 10cm incisions in the pastry, every 10cm – this will help the crust overlap and give a pleasing pattern.

Spread the béchamel into the middle of the pastry in an even layer but not over any of the cuts. Lay the pickled onions over the béchamel in an even layer. Mix together the pigs, carrots, parsnips, sprouts and roasties, season and pile into the middle of the pastry. Sprinkle over the crumbled blue cheese.

Fold up all of the outsides of the pastry, sealing in some of the veg, to make a crust, slightly overlapping the pieces of pastry. Brush the pastry with beaten egg then grate a little more cheese over the pastry.

Bake for 30-40 minutes or until the pastry is deep golden brown. Cool slightly, cut into wedges and serve with cranberry sauce.