Use a pestle and mortar to crush the coriander seeds, but don’t let them get too fine. Peel off long thick strips of lemon zest and place in a bowl with the olives. Squeeze the lemon then top with 3 times as much extra virgin olive oil. Add salt, pepper and the crushed coriander seeds. Pour the dressing over the olives and leave to marinate. The longer you leave them, the better they’ll taste.