The sap of maple trees was being used by Native Americans when the very earliest European immigrants arrived. Then it was an all-purpose seasoning, like salt, enlivening the austere diet. Now, with the refinement achieved by boiling and concentrating the flavor of the sap, maple syrup is a uniquely American sweetener. Here it adds just the right subtle note to a colorful puree of butternut squash.
1/4 cup (1/2 stick) butter
Preheat oven to 400°F. Place squash halves, cut side up, on large baking sheet. bake until very tender, about 50 minutes. Remove from oven and cool slightly. Using large spoon, scoop out squash flesh and transfer to large bowl.
Melt butter in heavy medium saucepan over medium-low heat. Add chopped onion and ground nutmeg and sauté until onion is tender and light brown, about 10 minutes. Transfer to bowl with squash. Add chicken broth and maple syrup. Puree mixture in batches in processor until smooth, occasionally scraping down sides of bowl. Season squash puree with salt and pepper. Return puree to same saucepan. (Can be prepared 4 hours ahead. Cover and let stand at room temperature.) Stir puree over medium heat until heated through. Transfer to bowl and serve.