Preheat the oven to 425. Peel and cube the butternut squash. Toss it with olive oil, salt, and pepper. Cook it in the oven for about 20 minutes, until soft.
While the squash is cooking, bring a pot of water to a boil. Cook the pasta according too its instructions, being sure to save at least 1 cup of the pasta water!
Put the cashews in a bowl and cover them with hot water. Let them soak for at least 5 minutes.
When the squash is soft, add it to a blender. Add the soaked cashews, pasta water, nutritional yeast, onion powder, garlic salt, paprika, lemon juice and olive oil. The amount of pasta water added depends on how thick or runny you want your sauce. Start by adding 1/2 cup and increase until you reach your desired consistency.
Blend everything until it is smooth then pour it over the cooked pasta. Top with salt, pepper, toasted breadcrumbs, and arugula.