COOK pasta as directed on package, omitting salt.
MEANWHILE, heat bacon in medium nonstick skillet on medium heat until crisp, stirring occasionally; drain. Add spinach; cook 2 min. or until wilted. Stir in Alfredo sauce and peas; cook and stir 1 min. on low heat or until heated through.
DRAIN pasta; place in large bowl. Add sauce mixture, bacon and cheese; toss to coat.