Clean the ambercup squash, cut it open, and remove the ends and the seeds. Cut the squash into bite-size pieces.
Peel and chop the onion coarsely. Fry the onion in a pan with 4 tablespoons of olive oil and the squash pieces on low heat until soft. If you use dry marjoram, add it to the pan so that it can develop its flavor.
Puree half the squash and onion mix with 1 tablespoon of olive oil and 3 tablespoons of nutritional yeast. If you use fresh marjoram, add it now so that it gets pureed. I’m using a food processor for this step, but an immersion blender would also work fine. The pureed sauce should have the consistency of a soft cream. If the sauce is too firm, you can add some water until it reaches the desired consistency.
Season the squash sauce with salt and pepper.
Cook the pasta al dente according to the packaging instructions.
Add the squash sauce to the hot pasta and mix gently.
Divide the pasta across plates and serve hot with the remaining squash pieces, roasted cedar nuts (or pine nuts), fresh parsley (or marjoram), and a drizzle of olive oil.