This is one of my favorite fall recipes. I got it from www.epicurious.com and tweaked it to make it a little bit healthier.
2 1/2 pounds butternut squash, cut into 1/2 inch cubes
2 tablespoons olive oil
4 cups skim milk
2 tablespoons dried rosemary, crumbled
2 tablespoon minced garlic
1/3 stick butter
4 tablespoons flour
1 box lasagna noodles
1 1/3 cups freshly grated Parmesan (about 5 ounces)
1 cup lite whipping cream (if you prefer, you can add 1 can evaporated skim milk to sauce and substitute sauce for top layer of cream).
Preheat oven to 425 degrees.
If you are using a whole squash, I would recommend purchasing one that is about 3 to 3 1/2 pounds. To ease peeling, stab squash once or twice to create a steam vent, then microwave for about 5-7 minutes. When cool enough to handle, peel squash and remove stringy pulp inside. Cut into small cubes. Toss with oil. Roast in pan about 20 minutes, flipping it midway through cooking time. Take out when turning golden brown and easily cut with knife. Reduce oven heat to 375 degrees.
When squash is roasting, simmer milk with dried rosemary over medium-low heat for 10 minutes (time starts when milk first starts to form bubbles, if starting to boil, turn heat down). Place strainer over medium bowl and strain milk.
Fill large pot with water. When boiling, add lasagne noodles and cook according to box directions, checking to make sure noodles do not stick to each other. Strain and set aside.
While pasta water is heating up, melt butter in large saucepan over medium heat. Add garlic and turn down to medium-low to avoid browning. Cook about 5 minutes or until softened. Stir in flours and stir continuously for 3 minutes. Pour strained milk into pan a little at a time, whisking into roux (flour/butter mixture). Cook additional 7-10 minutes over low heat, or until mixture thickens. Stir in squash and grind fresh black pepper to taste.
Grease a 13 by 9 inch baking dish.
Pour about 1/3 sauce into baking dish, spreading it around to cover bottom of dish. Cover with 3 lasagna sheets. Spread 1/3 of sauce over sheets and sprinkle with 1/2 cup Parmesan. Repeat for one additional layer.
If using whipping cream, use mixer to beat cream in large bowl until it holds soft peaks and spread evenly over top pasta layer, covering it evenly. If not using cream, use remaining sauce to cover top of lasagna.
Sprinkle remaining Parmesan cheese on top of lasagna. Cover with aluminum foil, tenting slightly to prevent it from sticking to lasagna. Bake for 30 minutes in middle rack of oven. Remove foil and bake additional 10 minutes, or until top is bubbling and turning brown. Remove from oven and let stand about 5-10 minutes before cutting.