Cook the spaghetti in generously salted boiling water to al dente and reserve some starchy pasta water before draining the pasta. Do not rinse the pasta!
The best way to grind the almonds is in a spice or coffee grinder. Mix the ground almonds, nutritional yeast, and garlic powder in a small bowl.
Once pasta is cooked, add olive oil to the same pot you cooked the spaghetti in over medium-low heat, and add the pasta and toss to coat well.
Add the almond parmesan mixture and a little pasta water a bit at a time until the pasta is well coated.
Add flakey salt, chopped basil, and fresh ground black pepper and serve immediately.