Genova, the capital of Liguria, is also the Capital of Pesto. The Genovese will tell you that only basil from Pra, much of it grown in glass houses, makes a decent sauce.
If you’ve got a food processor you can make pesto very easily, and it’s absolutely delicious freshly made. Here’s how to do it:
2 C packed basil leaves
1/3 C pine nuts (you may substitute walnuts, but they have a much sharper flavor)
2-3 cloves of garlic, coarsely chopped
½ C olive oil
½ C grated parmigiano cheese
salt and pepper to taste – but go easy on the salt as there’s a lot in the cheese and you don’t want any unpleasant surprises.
Toss everything in the food processor and whiz it around, stopping now and again to run a spatula down the sides of the processor bowl. Stop processing it when the pesto has reached the consistency you like – some people (we are among them) prefer it coarser than others.
Before the invention of food processors pesto was made by putting smaller quantities of the above ingredients in a mortar one at a time and grinding them together with a pestle. Our friend G still does it that way, while the water comes to a boil and the pasta is cooking. It really doesn’t take any longer to do it the old-fashioned way, it just requires a little more muscle. It’s the best we ever ate. (There’s a good mortar and pestle recipe in the Pruess article below.)
Use your pesto immediately! The local stores know how to keep their pesto green, but we haven’t figured it out. Some have told us that you should never touch the basil leaves with metal, but we don’t think that’s the secret. If you discover how to keep the sauce green, let us know. One way to slow it from browning is to store it under a cap of olive oil. But eventually it will darken. It’s so good, though, it shouldn’t be an issue as it will all be eaten up.
If you want to know more, here is a good article by Joanna Pruess that will give you additional info, plus some recipes in which to use pesto.