The thing is, nutritional yeast isn't really a great substitute for Parmesan's complexity. I think you need to add a little more finesse to replicate that salty, unami flavor for which Parmesan is known.
I also have an issue with the expense of pine nuts. Great tasting food shouldn't have to cost a lot to create.
I went with almonds instead. I would like to try a combo of walnut and almond in the future. I think you could really go crazy experimenting with various combos of nuts and seeds. There's the potential for so many wonderful variations on flavor and texture.
Sunflower seeds combined with various nuts and nooch really create great flavors.
At the time however, I had only almonds, so I forged ahead.
I'm also a big believer in how chiles make vegan food better. They add another layer of complexity without adding animal products.
A lot of pesto vegan and non use lemon juice. Acid adds that brightness that makes all the other ingredients come alive. I can't eat citrus. A lot of people can't. I went with capers instead. I thought their briny flavor would add that extra pop.
You'll need half a box of pasta. Cook it to al dente and set aside. Keep the pasta water in the pot.
2 cups fresh basil
3 tbls nutritional yeast
1/4 cup roasted almonds
1 serrano pepper
3 cloves garlic
3 tbls capers and brine
1/4 cup olive oil
1/3 cup reserved pasta water
2 tsp black pepper
2 tsps salt
Add all pesto ingredients to your food processor. Pulse until the big pieces are small. Scrape down the sides. Process until a paste is formed with only very small chunks.
I prefer the texture of this pesto. It's not smooth. It has bits and pieces. If you want a smoother pesto you can take the time to soak your nuts in water for a few hours, then drain. They will process to a smoother paste if you add this step. You may need to add more salt to your pesto as a result. You'll wash away any salt on the nuts.
Pour pesto over set aside pasta. Toss to coat.