Twist the coriander leaves away from the stalks and finely chop them. Add them to a non-metallic bowl along with the zest and juice of the limes, finely grated ginger, garlic and half of the sliced green chillies (try a little of the chilli to see how hot it is first – you may only need 1 chilli if very hot). Add the sugar and 1 tsp salt, and stir to dissolve. Cover the bowl and chill to let the flavours infuse.

Cut each cooked prawn into 3-4 pieces.

Add the chopped prawns to the lime marinade and toss well to coat. Cover and chill until cold.

Add the chopped onion, avocado and tomatoes. Roughly chop the coriander leaves and stir through the prawn salad, then pile onto a large sharing plate, scatter with the sliced chilli and serve with the tortilla chips for scooping.