Here’s the version we tried tonight: put 200g of walnuts, a clove of garlic a handful of parsley, a pinch of salt and freshly ground pepper in a food processor. Process until you have a rough paste. Then add a dinner roll or thick slice of bread, with the crust removed, soaked in milk and squeezed dry, olive oil, grated parmesan cheese and (if you have some on hand) a tablespoon of Greek yogurt. Start processing and, as the you process, add either milk, cream or ‘half-and-half’ through the funnel until the mixture forms a fairly smooth sauce. As in the case of pesto, however, you do not want a baby-food-like puree, so don’t over-process.
Take your gnocchi (see recipe for homemade potato gnocchi or just use store-bought) and boil them in well salted water until they come to the surface of the water. Transfer them from the water with a slotted spoon into a large bowl, add a generous dollop of the walnut sauce, some more grated cheese and, if you like–although some sources call it heresy–a nut of butter. Mix gently with a spatula, adding a bit of the pasta water to thin out the sauce if need be. Serve immediately with additional grated cheese for those who want it.
NOTES: Many recipes call for blanching the walnuts and removing their semi-bitter skins. I rather like the slightly bitter taste and understand from my research that it is more authentic not to do so. So I don’t. But if you are put off by the taste, by all means, you can add this extra step.
The use of a bit of Greek yogurt may seem, at first blush, rather odd. But the real salsa di noci is made with something called prescinsôea, a kind of fresh cheese which is more or less impossible to find outside Liguria. It has a slightly sour taste, which Greek yogurt, with a bit of parmesan cheese, is meant to approximate. (Any genovesi out there can tell us if this really works…!)
The most typical use of salsa di noci is to dress pansoti, or ‘pot bellies’, a kind of triangular Ligurian ravioli stuffed with cheese or cheese and an mixture of greens and herbs known as preboggion. But that’s material for another post. I find that walnut sauce works very well, especially in the summer, with potato gnocchi. Try it and see if you like it…