Butternut Squash Filling:

1. In a covered glass container microwave squash with 1/4 cup water on high for about 5 minutes or until tender. Drain squash and mash with potato masher or fork. Combine with butter/olive oil, ground sage, and maple syrup (optional) and set aside.

Sauce:

1. Combine whole-wheat pastry flour and 1/2 cup of milk in a small bowl and set aside. In a medium saucepan add olive oil and warm over medium heat. Add garlic and stir occasionally until garlic starts to brown. Add flour/milk mixture and whisk until smooth. Stir frequently and when the mixture starts to thicken, add remaining 2 1/4 cups milk. When sauce has thickened, remove from heat and add Swiss/Gruyere and Parmesan cheeses, salt, and pepper. Stir until the sauce is smooth.

Assembly and Cooking:

1. Preheat oven to 450 degrees F.
2. Grease an 8×8 baking dish with olive oil. Spread 1/3 cup of sauce in bottom of dish. Arrange 2-3 no-boil, whole-wheat lasagna noodles on top. Cover noodles with half of the butternut squash filling. Then add 1 1/2 cups spinach and drizzle with 2/3 cup white sauce. Repeat the following layers in this order: remaining lasagna noodles, butternut squash filling, spinach, and sauce.
3. Cover baking dish with oven-proof lid or foil. Bake for 15 minutes. Remove lid/foil and sprinkle with remaining 1/2 cup of shredded Swiss/Gruyere cheese and nuts (optional). Bake uncovered for an additional 10 minutes or until lightly brown and starting to bubble.
4. Remove from oven and let stand for 5-8 minutes. Garnish with chopped chives (optional).