It is not every day you meet someone who simultaneously makes you want to sit down and talk to them for hours, and also leap on the first train home, run to the vegetable garden and start making dinner. Jo, whom I met at the Barbican performing arts centre in London, is just such a person. She grows vegetables with such passion and energy, despite the limited space at her disposal.
This pesto is completely seasonal. Make it using whatever leafy greens you have, at any time of year – Swiss chard, soft herbs, sorrel and in the summer; rocket, kale, parsley and Asian greens in the winter. You can even use beetroot tops. The only rule is to make sure the leaves are as young and tender as possible – otherwise you will be chewing for days.