Macaroni and Cheese with Butternut Squash

Name: Macaroni and Cheese with Butternut Squash
Ingredients: 1 small butternut squash (about 1 pound), peeled, seeded, and cut into 1-inch cubes (about 3 cups); 1 cup homemade or low-sodium canned chicken stock, skimmed of fat; 1 ½ cups nonfat milk; Pinch of freshly grated nutmeg; Pinch of cayenne pepper; ¾ teaspoon coarse salt; Freshly ground black pepper; 1 pound elbow macaroni; 4 ounces extra-sharp cheddar cheese, finely grated (about 1 cup); 4 tablespoons Parmesan cheese, finely grated (1 ounce); 2 tablespoons fine breadcrumbs; 1 teaspoon olive oil; Olive-oil, cooking spray; ½ cup part-skim ricotta cheese