1. Roughly chop the mint and the parsley.
2. Process the herbs,garlic,pine nuts and oil together in a food processor or blender until you have a smoothish paste,then add the cheese and a splash of water and blitz briefly again.
3. Season with sea salt and a generous amount of black pepper.
4. Cook the spaghettini for seven to eight minutes. Meanwhile,put the zucchini in the bottom of a large saucepan. Lift the spaghettini out of the water and place it on top of the zucchini. Allow to sit off the heat for 30 seconds,which will allow the zucchini to soften. Add enough of the pesto to coat the pasta completely without drowning it (I usually have about a quarter left over),toss,then add the milk.
5. Let the pasta bubble over high heat for a minute to combine,add a little extra cheese and a splash of olive oil,if necessary,and toss through.
Check seasoning,sprinkle with the extra pine nuts and currants,and serve.
Tip: Keep any leftover pesto in an airtight jar for a week with a thin layer of oil over the top.