If using a fresh whole squash, peel and cut the squash into cubes. Measure about 4 cups (1 pound).
To cook in an Instant Pot: Add the squash and 2-3 cups of water, to cover, to your Instant Pot and cook on high pressure for 8 minutes. Carefully release the pressure and drain the squash.
To cook on the stovetop: Bring a large pot of water to a boil, then add the butternut squash cubes. Simmer for about 10-12 minutes, until the squash is fork tender. Drain.
Cook the pasta according to package instructions, being careful not to overcook. Drain and add the noodles back to the pot.
In a high powered blender, add the cooked butternut squash along with the cashews, 2 cups of water, cornstarch, nutritional yeast, dijon, garlic powder, onion powder, lemon juice and salt. Blend until very smooth.
Add the cheese sauce to the pot with the cooked noodles. Stir constantly over low-medium heat for a minute or two until the sauce thickens a bit. Serve immediately.
