This article is about basil pesto, the second most famous Italian pasta sauce, of course after tomato sauce.
However, this is not about the traditional way to make “Pesto Genovese” – using a mortar; there are plenty of good resources on that (as greatly summarized on Food Lover’s Odyssey). This article is about the more modern way to make pesto – using a blender, a method which is quite common also in Italy.
Technically the word “pesto” comes from the Italian ‘pestare’, to pound. Therefore, the purists would argue that this sauce should be called differently when made in a blender.
Aside from how it should be called, does the pesto made in a blender taste the same as the traditional one? Absolutely not. But it does get close, and it’s much better than any pesto that I could ever buy in a jar.
But before we start throwing basil leaves into the blender, it’s important to know that chopped basil is prone to oxidation – it turns dark and deteriorates in flavor when in contact with the oxygen in the air. Luckily oxidation can be countered by allowing the basil leaves to dry completely before blending them so that the oil can create a seal around the chopped leaves, keeping the oxygen away.
Basil also deteriorates and changes flavor when heated too much. To help counter this, the blender must be activated in pulses in order to limit the overall blending time and the corresponding friction produced by the blades. It also helps to chill the blender bowl and blade in the freezer before use.
- 100 g fresh basil leaves (if you can find it, prefer the Genovese kind)
- 50 g Parmigiano (or a mix of Parmigiano & Pecorino cheese)
- 25 g pine nuts (possibly, from the Mediterranean)
- ½ cup extra-virgin olive oil
- 1 teaspoon of coarse salt
- 1 clove of garlic (optional)
- Gently wash the basil under cold running water and then lay it on a towel and let it dry completely (fig. 1). Do not bend or crush the leaves.
- Meanwhile, put the blender's bowl and blade in the freezer for at least 10 minutes (fig. 2a).
- Pour all of the oil in the blender, then add the crushed garlic (if using it) and the basil. Give it a few pulses until the leaves are roughly chopped up (fig. 2b).
- Add the cheese, grated or cut in small bits, and the salt (fig. 2c). Give it a few more spins.
- Add the whole pine nuts (fig. 2d).
- Give a few last spins and extract from the blender (fig. 3).
If the sauce is not used immediately, it can be preserved in the fridge for up to two to three days. Store it in a tall and narrow container (e.g.: a glass) and top it up with an extra tablespoon of olive oil. Before using it, leave the sauce out of the fridge an hour - don't warm it up, or you'll cause the cheese to lump together and separate from the oil. Pesto can also be frozen, in that case some recommend not to add the cheese until the sauce is thawed.