Preheat oven to 350. (Now is also a good time to start soaking your cashews if you haven't yet!)
Cook pasta: Cook pasta according to package directions. When pasta is done cooking, be sure to reserve 1 cup of the pasta water before draining the pasta.
Make your Butternut "Cheese" Sauce: Drain your soaked cashews. Add your cashews, ¾ cup of the reserved pasta water, and all other ingredients for the Butternut "Cheese" Sauce to the blender. Blend until smooth and add more of the pasta water IF NECESSARY for consistency.
Make your Breadcrumb Mixture: Combine all ingredients for the breadcrumb mixture, except the plant milk, to a small bowl. Mix to combine. Once evenly incorporated, add in the plant milk and mix. After a minute or two of mixing, the plant milk should cause the mixture to become slightly darker and create slightly larger clumps.
Assemble: In a large bowl, combine the pasta and the Butternut "Cheese" Sauce. Stir to combine. Add this mixture to an 8x8 baking dish. Sprinkle your breadcrumb mixture on top of the pasta.
Bake: Bake at 350 for 20-25 minutes, or until the breadcrumbs become slightly golden. Be careful not to overbake or it could dry out!
Let cool just a few minutes and serve! Sprinkle on some optional vegan parmesan before serving if you'd like, but it's also delicious on its own!