Put the salmon flesh side down in a large cold non-stick frying pan and place on a medium-high heat. As the pan comes up to temperature and the salmon begins to sizzle (about 3 minutes), flip it over and cook on the skin side for 5 minutes, or until very crisp and just cooked (depending on its thickness).
Meanwhile, halve the cherry tomatoes, tear up most of the basil leaves, then toss it all with 1 tablespoon of red wine vinegar and a pinch of sea salt and black pepper. Squash the olives and discard the stones, then finely chop the flesh. Mix with 1 teaspoon of extra virgin olive oil and a splash of water.
Finely slice the chorizo, add to the pan for the last 2 minutes, then toss in the dressed tomatoes for 30 seconds. Divide between your plates, with the salmon on top. Spoon over the dressed olives and pick over the remaining basil.