Preheat your oven to 425 degrees F.
In your blender, add in all pumpkin cheese sauce ingredients. Please note that if you did not soak your cashews overnight, you can easily soak them in hot water for about 15-20 minutes prior to using. Be sure to drain well when done.
Blend pumpkin cheese sauce until smooth and creamy. Taste, and adjust seasonings if you'd like.
While the oven is still preheating, cook the pasta according to the package's instructions. The pasta should be al dente when done. Drain the water from the pasta.
Mix cooked pasta with pumpkin cheese sauce until evenly coated. Pour into a glass casserole dish to bake in the oven. Bake at 425 degrees F for 25-30 minutes.
While mac and cheese is cooking, make your sunflower crumble. Combine sunflower seeds and nutritional yeast into a food processor and process until the pieces are small and crumbly. Taste, and adjust salt if needed.
When mac and cheese is done, take it out of the oven and add on a sprinkling of the sunflower crumble. Put mac and cheese back into the oven and broil for about 2-3 minutes, or until sunflower crumble is just toasty.
Serve pumpkin mac and cheese in bowls with a sprinkling of parsley.
Enjoy!