Smoked haddock in puff pastry

• puff pastry, made using 8 oz (225 g) strong white flour
• beaten egg, for glazing

Cut the haddock in large pieces and poach in milk to cover for about 10 minutes. Sprinkle the rice into a saucepan of boiling salted water and simmer for 8–10 minutes until tender. Meanwhile, peel and finely chop the onion. Trim and coarsely chop the mushrooms and chop the hard-boiled eggs. Drain the rice and put into a mixing bowl. Drain the fish and when cool enough to handle, flake the fish,