How to Make It
Preheat oven to 400°.
Combine squash, 1 tablespoon olive oil, salt, and pepper on a baking sheet; arrange in a single layer. Bake at 400° for 15 minutes or until tender. Add walnuts to baking sheet; bake at 400° for 5 minutes or until toasted. Cool slightly; coarsely chop walnuts.
Cook pasta according to package directions, omitting salt and fat. Drain.
Combine remaining 1 tablespoon olive oil, stock, vinegar, and garlic in a large skillet over medium-high heat; simmer 8 minutes or until reduced to 1/2 cup. Combine pasta, squash mixture, walnuts, stock mixture, parsley, and sage in a large bowl; toss to coat. Sprinkle with cheese.