1Cook and drain pasta as directed on package.
2Meanwhile, in large skillet or Dutch oven, heat oil and rosemary over low heat at least 15 minutes. Remove and discard rosemary. Add chicken to skillet; cook over medium heat 2 to 3 minutes until warm.
3Add cooked pasta and spinach; toss. Cook 2 to 3 minutes or until spinach begins to wilt. Season with salt and pepper.