Season the fish with salt and pepper, then put in a saucepan with the cumin, oregano, garlic and
enough stock to cover.
Bring to the boil and boil for 1 minute. Remove the saucepan from the heat and let the fish cool
in the cooking liquid for about 30 minutes.
Remove the fish with a slotted spoon. Flake the fish into bite-sized pieces and put in a
non-metallic bowl. Sprinkle with the lemon juice and set aside.
Heat the tortillas in a dry non-stick frying pan over a medium heat, sprinkling with a few drops
of water as they heat; wrap in a clean tea towel as you work to keep them warm. Alternatively, heat
through in a stack in the pan, alternating the tortillas from the top to the bottom to warm
Arrange some lettuce in the centre of 1 tortilla, spoon on a few fish chunks, then sprinkle with
a little tomato. Top with some salsa. Repeat with the other tortillas and serve immediately,
garnished with lemon wedges.