3 chillies, split lengthways and deseeded
large handful coriander, finely chopped
2 medium onions, sliced
1 tsp freshly ground black pepper
½ tsp ground coriander
½ tsp ground cumin
1 tsp mustard seeds
1 tsp paprika
½ tsp salt
1 tsp fine sea salt
½ tsp ground turmeric
7 tbsp vegetable oil, for frying
3 tilapia fillets, sliced lengthways (alternatively, you could use cod, haddock or any white fish fillets)