Pesto seems to be a more and more loosely used word to describe any sauce using greens, nuts of some kind and oil. To me Wild Pesto is just another way of getting wild green goodness into you and also extending its shelf life a bit. So..
You will need.
A few handfuls of wild greens
Olive oil (or any oil you care to use)
Parmesan (if you like)
I have taken inspiration from a wonderful Japanese Blog called Shikigami and decided not to go down the blender route. Instead take a handful of geens onto your chopping board and start chopping. When nice and fine add another handful on top. This does take longer than using a blender but it gives a really good consistency. Keep chopping and add your nuts more greens and eventually your cheese if you are using it. When everything is finely chopped transfer to bowl and add your oil. Eat immediately and place anything left over in a jars. Yum.