• Heat the oven to 220C/fan 200C/gas 7.
  • Tear the chicken fl esh from the bone in large chunks and discard the skin and bone.
  • Heat the butter in a large pan and add the spring onions.
  • Cook for a few minutes until softened. Add the mushrooms and cook for 5 minutes or so, until lightly coloured.
  • Stir in the fl our, and cook for another minute, then gradually add the milk.
  • Add the cream, simmer until the sauce thickens. Stir in the chicken and tarragon.
  • Roll out the pastry to the thickness of a 20p and cut 4 circles big enough to cover 4 small pie dishes.
  • Divide the chicken mixture between the dishes and brush the rims with beaten egg.
  • Lift the pastry on to the pies, trimming off any excess. Press down and crimp the edges with a fork. Cut a couple of slits in the pastry to let the steam out and brush all over with the rest of the egg.
  • Bake for 15-20 minutes, until the pastry is crisp and golden brown.