Pop all the ingredients into a food processor and whizz until the pieces are nice and small and the texture is relatively smooth. I still like a few small chunks, so I stop before it becomes more like a purèe.
Transfer the mixture to a small, sterilized jar or an airthight container, or divide it between two ramekins and cover.
This tapenade keeps for at least a week in a sealed container in the refrigerator. It is also suitable for freezing in portions. If you do freeze it, defrost it slowly in the refrigerator and taste before you serve it – you night like to ad a little more basil or a squeeze more lemon juice.