Mix together cumin, coriander, paprika, and a pinch of salt in a large bowl, then add the juice from one lime. Toss in the fish fillets and cover, then set aside.
Finely slice the cabbage, and squeeze lime juice over it and season with salt. Set that aside, then chop the tomatoes into small pieces, leaving it on the cutting board.. Scoop out and mash up your avocado on the cutting board, then squeeze on lime juice and sprinkle in some salt.
Heat your grill to high, and line a baking tray with foil. Brush on some olive oil, then place the fish fillets on the tray, pouring any excess lime paste on the fish. Cook the fish for 8 to 10 minutes until it’s cooked through.
Warm your tortillas by wrapping them in foil and placing them in the oven for a few minutes. To serve, spread a little sour cream over the tortillas and top with cabbage, tomatoes and avocado. Flake the fish and add a few chunks to the tortilla, then top with coriander, chilli and chilli sauce.
