Slice the sea bass into thin strips using a sharp knife. To cure the fish, place the slices in a glass bowl and season with salt and pepper. Pour in the lime juice, then add the zest, onion and fresh chilli and tear in half the coriander leaves.
Place these slices in a bowl or dish and session with salt and pepper.
Squeeze over 8 limes and then add the zest of 2 limes.
Stir through the thinly sliced onion, fresh chilli and a portion of chopped coriander leaves
Add a handful of ice cubes to the bowl and cover with cling film. Leave at room temperature until the ice has melted and the fish has turned opaque.
Meanwhile, warm the fresh soft blue corn tortillas in a dry pan, flipping them to ensure each side colours but remains soft
Top each warm tortilla with the ceviche and sprinkle over the shredded lettuce and a spoonful of tomatillo salsa. Add a garnish of sliced red chillies if you like it hot.