I'm pretty sure I've said this to you before... OK, I've probably said this to you ad nauseum... but this bears repeating (which also happens to be the tag line from my favorite birthday card ever)...
At least once every summer, you need to make fresh pesto using a mortar and pestle. I know, I know, it sounds like a pain. But it's really kind of fun, and you can imagine the face of someone you're mad at as you pound...
Never mind.
The food processor is just fine and makes a perfectly acceptable sauce...
But... here's where you need to trust me... pounded pesto is a completely different animal and for scientific reasons I don't pretend to understand...
The flavor is totally different and wildly superior.
Pound your garlic with some of your best coarse salt until it's starting to look liquid. Then add and pound the basil a handful at a time.
When it starts to look like pesto, toss in some nuts (pine or walnut) and pound again.
When you feel it's puréed enough to your liking, start adding some good EVOO and stir.
No more pounding unless Jackson Pollock is your hero.
Stir in some Parmigiano (reserving more for the top), thin this with a bit of pasta water, and toss with perfectly al dente pasta.
Add more cheese. Taste for salt. Then eat as if there's no tomorrow.
In honor of all the work this takes, I serve it with homemade pasta as well... might as well go whole hog!
PS. As I'm sure you remember, my favorite mortar and pestle is actually a Japanese suribachi... A gorgeous, simply glazed wide bowl with an unglazed deeply ridged interior surface and a wooden pounder. Very inexpensive. Easy to find in any Asian store. And mine is entering its third decade!
PPS. A side of sliced heirloom tomatoes with a little sea salt is perfect with this.