Hot and sour curried cod pie

Method

1. Sprinkle salt all over the cod and set aside for 15 minutes. Rinse well in cold water, pat dry with kitchen paper, then put in the fridge.
2. Heat the oil in a large frying pan for 1 minute over a medium heat. Add the mustard seeds, sizzle for 30 seconds, then add the onions and a pinch of salt and cook for 10 minutes until the onions are well cooked and starting to colour. Add the garlic and chillies and cook for a further minute before adding the dry spices and cooking for another minute. Add the tomatoes and tamarind and cook for a further 10 minutes, then stir in the coriander and set aside to cool (see Make Ahead).
3. Once cool, add the cod to the filling and spoon into a shallow ovenproof dish just large enough to hold the mixture.
4. On a lightly floured surface, roll out the pastry into a 1cm thick disc. Brush the outside lip of the dish with a little of the egg wash and lay over the pastry disc, pressing it against the lip to seal. Trim off anything beyond a 2cm overlap with a small knife. Brush the pastry with the remaining egg and sprinkle over the fennel, sesame seeds and a touch of sea salt. Chill for 20 minutes.
5. Heat the oven to 220°C/200°C fan/ gas 7. Put the dish in the hot oven and bake the pie for 25-30 minutes or until golden. Remove from the oven and serve with steamed broccoli tossed in a little butter and sprinkled with toasted almonds.