Also known as salsa all' agresto, this Italian sauce dates back to the Middle Ages. It has some similarities to pesto, in that it is a paste made from herbs, nuts and oil, but that is where the comarisons end. Agresto sauce includes verjuice (agresto itself refers to unripe grape juice) as a main ingredient and when combined with a variety of nuts it provides an intriguing flavour that is a glimpse of what people ate hundreds of years ago.
Traditionally it was served with boiled meats, but don't limit yourself. Try it with anything you would use pesto for, such as a topping for bruschetta or tossed through freshly cooked pasta. If you cant find verjuice, try a mix of white wine vinegar, lemon juice and a little sugar.
1 cup almonds
1 cup walnuts
2 garlic cloves, peeled (or use garlic oil)
3 cups parsley leaves, washed and dried (about 2 bunches)
½ cup basil leaves
¾ cup extra virgin olive oil
¾ cup verjuice
Roast the nuts in a pre heated 200° C (390° F) oven for about 15 minutes. Rub the walnuts to remove the skins. In a food processor, blend the nuts, garlic and herbs together until roughly chopped. With the motor running, add the oil in a thin stream, then do the same with the verjuice. Taste for salt and pepper. If you are feeling particularly energetic, you could make this sauce in a mortar and pestle.
Cover the surface of the sauce with a film of olive oil (to stop oxidization) and it will last a week in the refrigerator.