Gather together all of your ingredients and heat a large, heavy-bottomed frying pan over a high heat.
Place the tomatoes, garlic and chilli in the dry frying pan and dry roast until they are blackened, blistered and soft. The tomatoes will take a little longer, so remove the garlic and chilli first as they are cooked (about 5 to 10 minutes).
Remove and discard the stem from the chilli and the skin from the garlic and put both in a pestle and mortar. Pound to a paste, then add the tomatoes and work them into the chilli.
Add the coriander, onion and lime juice. Taste and check for seasoning.