Macaroni and Four Cheeses

I got this recipe from Eat Smart with Ellie Krieger. It's a little cookbook magazine thing from Fine Cooking. Anyway, it's a healthier version of Mac and Cheese and it was super easy and pretty tasty. Since it's a healthier version it doesn't use as much cheese - next time I make it I might throw in a bit more.
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Cooking spray
One 16-oz box elbow macaroni
Two 10-oz packages frozen pureed winter squash (yep - that's right!)
2 cups low fat milk
1 1/3 cups grated extra sharp cheddar cheese
2/3 cup grated Monterrey jack cheese
1/2 cup part-skim ricotta cheese
1 tsp salt
1 tsp dry mustard
1/8 tsp cayenne pepper
2 tbsp plain dry bread crumbs
2 tbsp freshly grated Parmesan cheese
1 tsp olive oil
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Preheat oven to 375. Coat a 9x13-inch baking dish with cooking spray.

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Cook the macaroni according to the package directions. Drain and transfer to the prepared baking dish.
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Meanwhile, place the frozen squash and milk in a large saucepan and cook over low heat, stirring occasionally and breaking up the squash with a spoon until it is defrosted. Turn the heat up to medium and cook until the mixture is almost simmering, stirring occasionally. Remove the pan from the heat and stir in the cheddar, jack cheese, ricotta, salt, mustard and cayenne. Pour this mixture over the macaroni and stir to combine.
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Combine the bread crumbs, Parmesan, and oil in a small bowl. Sprinkle over the macaroni and cheese. Bake until the cheeses are bubbling around the edges, about 20 minutes, then broil for 3 minutes so the top is crisp and nicely browned.
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Serves 8, serving size 2 cups.
Per serving:
390 calories
11 grams fat: 1 mono, .5 poly, and 6 saturated
18 grams protein
56 grams carbs
3.5 grams fiber
35 mg cholesterol
547 mg sodium
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*** I could not find frozen squash for the life of me! So I bought two butternut squash, cut them in half, and baked them until they were soft (about an hour). Then I scraped the pulp out and mashed it up. This worked great.