Makes enough for 6

This lovely textural, creamy, salty sauce is perfect for all the inky green vegetables that begin to make their appearance in early autumn. This sauce is best made on the day it is to be eaten.

2 good-quality anchovies
1 clove of garlic, peeled and finely chopped
1 small bunch of flat-leaf parsley
A handful of shelled walnuts, finely chopped
100ml/31/2fl oz extra-virgin olive oil

Pound all the ingredients except the oil in a pestle and mortar until smooth, then pour in the oil and stir well to combine. Spoon over any lightly cooked green vegetable, such as broccoli, spinach or chard.