Everyone these days knows about pesto, the Genovese basil sauce, but it is rarely well made. The first thing to know about pesto--and I have this from a Genovese friend--is that the real thing is redolent of garlic. The flavors should explode in your mouth. Too many versions you'll come across (including anything you might buy in a jar) are timid imitations of the real thing.
In the age of food processors, pesto is simplicity itself to make. You throw in some garlic cloves--don't be shy--and pulse a few times, until the garlic is minced fairly well. Then add several handfuls of basil, a handful of pinoli, salt, pepper and a generous amount of olive oil. Whiz that around (always using the pulse button) until you have a rough paste. Another common mistake: don't over-process. Pesto should have texture, with each element still perceptible to the eye and tongue. Then add grated pecorino cheese, or a combination of pecorino and parmigiano if you prefer--but never only parmigiano, which would not stand up to the assertive flavors of the garlic and basil. Pulse just enough to blend the cheese into the pesto. If the pesto is quite thick, add more olive oil and pulse again, repeating until you have the consistency that you want--the pesto should be thick, but just barely 'pourable'. I won't give measurements because I never measure and, in any event, the exact proportions are a matter of taste.
The classic pasta for pesto is trenette. There is some confusion over what trenette actually are. They are often taken as being the same thing as fettuccine or tagliatelle. Trenette are somewhat like linguine but rather plumper. But in a pinch, any of these pastas would work as a substitute. Pesto is also often eaten with trofie, another typical homemade Genovese pasta that looks a bit like a corkscrew. Here's the way to make it.
Trenette al pesto typically includes green beans and thinly sliced potatoes, which are cooked along with the pasta in salted water and then mixed well with the pesto before serving. If you haven't try pesto this way, do yourself a favor--it's a fabulous combination. You can top it with additional grated cheese if you like.
NOTE: If you want to make pesto the old fashioned way (and purists will tell you that real pesto can only be made this way), break out your mortar and pestle. (The word pesto, in fact, used to mean pestle in Italian, although it's now called pestello in modern Italian. And mortar is mortaio, in case you're interested.) In any event, start with your garlic and a pinch of salt and starting mashing the garlic. When it's a paste, add the pinoli, mash them, to a paste then start adding the basil leaves, little by little, crushing them into a paste before adding the next handful, adding oil as you go. Then add your cheese and test for seasoning. It's a lot of effort and, to my taste at least, not really worth it. But do try it once just to know what the real, real thing is like.