1. In a 10-inch sauté pan, melt the butter. Whisk in the flour and let cook for 2-3 minutes until golden. Slowly add the half and half to the pan, whisking to combine until all has been added. Add the butternut squash puree and whisk to combine. Cook, whisking occasionally, until thickened 5-7 minutes.
2. Add the Romano cheese, a handful at a time, whisking to combine. Continue until all the cheese has been added.
3. Season the sauce with salt, pepper and nutmeg, tasting as you go. Add additional salt and pepper, as desired.
4. Add the cooked pasta to the pan and toss to combine. Serve immediately.
If desired, serve with a light sprinkle of romano, sea salt, pepper and nutmeg.