Preheat the oven to 400 degrees Fahrenheit.
Take the both whole heads of garlic and cut off the top part so you can see the inside of each clove.
Drizzle with 1 tbsp of olive oil, wrap tightly in foil, and place in the oven.
Roast for 45 minutes.
During the final 10 minutes, bring a large pot of water to a boil.
Cook pasta according to package instructions.
When the garlic is done, let cool until it is easy to handle. Squeeze the bottom so the cloves come out into a blender. This is something that you'll find either oddly satisfying or totally not appealing, depending on who you are :) Careful not to get any of the skin in there.
Add all remaining ingredients except for the nutritional yeast.
Process the mixture until completely smooth.
Transfer the sauce to a large pan and heat over low heat. Whisk in the nutritional yeast. Let simmer for about 5 minutes to allow the sauce to thicken. When it starts to thicken, stir in the pasta and allow the sauce to continue to thicken.
Taste and add more salt, pepper, nutritional yeast, butter, or cashew parmesan as desired.