Cut the halibut fillet into cubes measuring 1 x 1 cm.
Put in a bowl, and add the juice from one freshly squeezed lime. Cool in fridge for 10 minutes.
In the meantime, prepare the other ingredients. Chop mango into small cubes. Finely chop the red onion and chili. Mix all ingredients together, and add a pinch of salt.
Enjoy with crispy toast or tortilla chips.