You can substitute sour cream for creme fraiche.

5 cups (1/2-inch) cubed peeled butternut squash $ 1 tablespoon olive oil $ Cooking spray $ 12 ounces uncooked ziti (short tube-shaped pasta), campanile, or other short pasta 4 cups chopped kale 2 bacon slices $ 2 cups vertically sliced onion $ 1 teaspoon salt, divided 5 garlic cloves, minced 2 cups fat-free, lower-sodium chicken broth, divided 2 tablespoons all-purpose flour $ 1/2 teaspoon crushed red pepper 1 cup crème fraîche 1/3 cup (about 1 1/2 ounces) shredded Gruyère cheese

1. Preheat oven to 400°.
2. Combine squash and oil in a large bowl; toss well. Arrange squash mixture in a single layer on a baking sheet coated with cooking spray. Bake at 400° for 30 minutes or until squash is tender.
3. Cook pasta 7 minutes or until almost al dente, omitting salt and fat. Add kale to pan during last 2 minutes of cooking. Drain pasta mixture.
4. Cook bacon in a large nonstick skillet over medium heat until crisp. Remove bacon from pan; crumble. Add onion to drippings in pan; cook 6 minutes, stirring occasionally. Add 1/2 teaspoon salt and garlic; cook 1 minute, stirring occasionally.
5. Bring 1 3/4 cups broth to a boil in a small saucepan. Combine remaining 1/4 cup broth and flour in a small bowl, stirring with a whisk. Add flour mixture, remaining 1/2 teaspoon salt, and pepper to broth. Cook 2 minutes or until slightly thickened. Remove from heat; stir in crème fraîche.
6. Combine squash, pasta mixture, bacon, onion mixture, and sauce in a large bowl; toss gently. Place pasta mixture in a 13 x 9-inch glass or ceramic baking dish coated with cooking spray; sprinkle evenly with cheese. Bake at 400° for 25 minutes or until bubbly and slightly browned.