Preheat oven to 425F. Cut the squash in half and scoop out seeds. You can either roast it in halves or in cubes (which will be faster but more cutting). In a casserole dish cover squash with olive oil, salt and pepper Roast for about 40 minutes (chopped) or 60 minutes(halved), uncovered, or until tender
To prepare the cheeze sauce use a blender or food processor and add Earth balance, nutritional yeast, Dijon, garlic, lemon, S & P. Then in a bowl, whisk together milk and cornstarch or flour until clumps are gone. Add into blender along with 1-2 cups of roasted squash (cooked carrots work too!)
Cook your pasta according to package directions.
Add cooked, drained, and rinsed macaroni & leaves into pot, along with cheeze sauce & mix-ins. Heat and serve. Recipe adapted from http://ohsheglows.com/2011/10/03/butternut-squash-mac-n-cheeze