Heat the oil in a pan and sauté the onion, garlic and spices for 5 minutes until softened and fragrant.
Add the rice, water, bay leaf and salt, then cover and simmer for 15 minutes. Remove the bay leaf and add the coriander, chilli, zest and lemon juice.
Roll one of the pieces of pastry out on a lightly floured surface to a 20cm x 15cm rectangle. Season the salmon well on both sides.
Place the rice down the middle of the pastry then place the salmon on top.
Roll out the remaining piece of pastry to 20cm x 15cm and use a lattice cutter to cut out a lattice. Place the lattice pastry on top of the salmon.
Trim the sides and fold the edges of the pastry over to seal it well. Brush with the egg yolk.
Preheat the oven to 220˚C, gas mark 7.
Bake the pie in the oven for 10 minutes, then turn the oven down to 180˚C, gas mark 4, and continue to bake for about 15 minutes until the pastry is golden brown.
Serve warm or cold.