*Nuts and seeds: I’ve used a variety of raw nuts and seeds, from cashews, walnuts, pine nuts, and pecans to sunflower seeds or a mix of several. For my last batch, I used a combination of cashews and sunflower seeds. Although you may toast the raw nuts first, I usually skip this step and do not find the flavor to be lacking.
**The precise amount of oil depends on how thick or thin you’d like the final pesto to be. I prefer the consistency of a spread (perfect for pesto bread, pizza, or spreading on salmon or chicken), which can easily be thinned with pasta cooking water, broth, white wine, or even water when a thinner condiment is desired.
***I like to freeze the fresh pesto in small jars (about ¼-½ cup in size), but you may also freeze it in ice cube trays. In this case, transfer the pesto cubes to an airtight freezer bag or storage container once frozen. Small containers of pesto thaw rather quickly, and the process can be expedited by soaking the container in a bowl of cool water.
Extras: As noted, cheese is purely optional in this recipe. I have used it, but more times than not, I skip it. If you choose to use it, you could go with classic Parmesan or branch out with another hard cheese like asiago. Or use nutritional yeast for a vegan alternative. Herbs are a lovely addition if you have them. When lucky enough to have pea greens to use as the pesto base, I snip a sprig or two of mint from my garden, as the flavor complements beautifully. Similarly, basil, parsley, and even a small amount of chives add bright, fresh flavor to various other greens. Finally, if you’re feeling industrious, you could grate the zest of one lemon into the bowl of the food processor for more lemony flavor without additional tartness. Rest assured, however, that the pesto is fantastic as is!
Using with pasta: I find ½-cup portions to be the perfect amount for 8 ounces of pasta. When making thicker pesto with less oil, as I do with this recipe, I thin the thawed pesto with some of the pasta cooking liquid before tossing it with the cooked and drained pasta. Simple pesto pasta is delicious as is, although a handful of halved grape or cherry tomatoes or slow roasted tomatoes, a sprinkle of nuts or seeds, a cup or so of leftover, chopped chicken or shrimp, roughly chopped baby spinach, and/or some slivered, fresh basil will create an especially delightful meal.
Tip: I recently mentioned my newfound trick that prevents leftover guacamole from turning brown: simply placing a slice or two of peeled onion in the bowl and covering it magically maintains the dip’s bright green color. (No need to completely cover the surface with the onion; just lay the onion on top.) Since leftover pesto tends to brown, too (it will still taste great, by the way), I recently stored an unused portion with a wedge of onion. To my delight, the pesto remained green! Alternatively, a thin lemon slice placed on the surface helps to maintain the fresh color.