Peel and cut a red onion in half, cut it lengthwise into slices. In a pan on the stove, add the butter and onions. Sauté the onions in the butter on medium heat until softened. Add a pinch of salt and pepper to taste. Take it off the heat.

Peel the butternut squash, cut off the ends and cut it in half. Scoop out the seeds, cut each halve down the middle and cube it. You can cut the squash anyway you like as it will be boiled and blended into the sauce regardless.

Take a pot and fill it with water and broth. You can also use all water or all vegetable broth as this recipe is very versatile. Let it come to a boil and add in the cubed squash. Boil until fork tender.

With a slotted spoon take out the squash and add it to a blender with the sautéed onions and butter. Grate the cheese, and add it in with a ladle of the squash broth. Blend until smooth. You can adjust how thin or thick you like it by adjusting the broth. Taste and adjust for salt.

In the meantime, boil the pasta as per the package directions. I like to boil mine in boiling salted water until al-dente. Once cooked, strain the pasta. Add the pasta into a dish and pour the sauce on top. Mix and enjoy!