Score a cross into the base of each tomato with a sharp knife and place in a large bowl. Pour over boiling water to cover and leave for 20 seconds. Transfer the tomatoes to a bowl of iced water using a slotted spoon and allow to cool slightly. When cool, peel off the skins. Cut the tomatoes in half, remove and discard the seeds and chop the tomato flesh.
Juice the lime with the red pepper. Transfer the juice to a bowl.
Add the chopped tomatoes to the juice along with the chilli, red onion and coriander. Stir to combine and season to taste. Serve with tortilla chips.