This was adapted from an Ellie Krieger recipe. I made a few of my own tweaks. A friend of mine challenged me to find a mac & cheese recipe that wouldn't leave us feeling like we ate our entire body weight in fattening dairy. I know it sounds strange to use squash as the base for the cheese sauce, but it actually worked. The dish doesn't taste like squash. It's nice and creamy with a crispy, browned top. If you're looking for a light alternative to many people's favorite comfort food, give this a try.