Whole Wheat Rotini with Walnut Pesto

In food processor with knife blade attached, blend walnuts, parsley, Parmesan, lemon juice, garlic, 1/4 cup water, 1/2 teaspoon salt, and 1/4 teaspoon freshly ground black pepper until pureed, stopping processor occasionally and scraping bowl with rubber spatula. Set pesto aside. Meanwhile, heat large covered saucepot of salted water to boiling on high. Add pasta and cook as label directs. While pasta is cooking, sprinkle chicken with 1/4 teaspoon salt to season all sides. In 12-inch nonstick skillet, heat 1 teaspoon oil on medium 1 minute. Add chicken, and cook 6 to 7 minutes or until chicken loses its pink color throughout, stirring occasionally. Transfer chicken to bowl; keep warm. To same skillet, add red pepper and remaining 1 teaspoon oil, and cook on medium 3 minutes. Add asparagus and 3 tablespoons water; cover and cook 6 to 7 minutes or until tender-crisp, stirring occasionally. Reserve 1/2 cup pasta cooking water. Drain pasta and return to saucepot; stir in chicken, vegetables, pesto, and reserved cooking water; toss to coat.