Another thing, Genovese pesto is famous in part because it is often made with young, small basil leaves. For us non-Italians it is easy to find Genovese basil in stores and at farmer’s markets particularly in the summer, but chances are it wasn’t picked young. I wouldn’t worry about it too much, simply by hand chopping all your ingredients, you will see a major shift in personality of your pesto. If you grow your own basil, I’m envious.
If you’re serious about making good pesto, using this technique, get a good, sharp (preferably large, single blade) mezzaluna, or a good knife – you’ll need it. Chopping the ingredients will take twenty minutes or so. Whatever you use to chop, make sure it has a sharp blade or the basil will turn dark. Once you chop your ingredients, you’ll form them into a cake, pictured above. You add olive oil to this cake, and it’s magic – below.
Store any pesto you might use in the next day or two, refrigerated, under a thin film of olive oil. You can also freeze it in snack-sized baggies. Thaw and toss whatever gnocchi or pasta you like with it.
One key to perfect pesto is chopping all the ingredients by hand, preferably with a sharp mezzaluna or knife. This pesto will keep a bit in the refrigerator, but it really hits its peak when served soon after it is made. The technique here is: chop a bit, add some ingredients, chop some more. I think part of the reason she does it this way (instead of chopping everything all at once) is because some things get chopped into oblivion, while some, not as much – it encourages spectrum of cut sizes throughout the pesto contributing to the overall texture. All told, the chopping took me a leisurely twenty to thirty minutes, I wasn’t in any particular rush. You’ll also notice this recipe doesn’t have any added salt (just the saltiness from the cheese), make sure your pasta water is well salted if you are going to use this pesto on pasta or the overall flavor profile will fall flat. Also, be sure to adjust for seasoning before serving. With food this simple, you need to get the seasoning right. Trust your tastebuds.
Cover the pesto “cake” with a bit of olive oil. It doesn’t take much, just a few tablespoons. At this point, you can set the pesto aside, or place it in the refrigerator until you are ready to use it. Just before serving, give the pesto a quick stir to incorporate some of the oil into the basil. Francesca’s mom occasionally thins the pesto with a splash of pasta water for more coverage, but for our gnocchi this wasn’t necessary.