Wild mushroom koulibiacs

Method

• step 1

  Cut the pastry block in half and roll one half out into a neat rectangle. Cut it into 4 smaller rectangles and lay them on a buttered baking sheet.

• step 2

  Heat a good knob of butter in a frying pan and fry the leek gently until it's tender without letting it brown. Season well and tip into a bowl with the rice. Heat another knob of butter and fry the mushrooms with the garlic until they are tender and beginning to brown. If lots of water has come out of the mushrooms then turn up the heat and bubble it off. Season well, tip into the rice and fold everything together.

• step 3

  Divide the rice between the pieces of pastry. Roll out the remaining piece of pastry and cut it into 4 rectangles just bigger than the bases. Lay a lid on each pastry base and seal the edges. Cut a steam hole in the lid of each and brush the top with the egg. Chill for 30 minutes, or until 40 minutes before you want to serve them.

• step 4

  Heat the oven to 200C/fan 180C/gas 6. Bake the koulibiacs for 30-40 minutes or until the pastry is browned, puffed and cooked through.

• step 5

  Mix the mustard into the cream and spoon a little carefully into each steam hole and serve the rest on the side.