Heat oven to 400 degrees F. Cut tortillas into 1/2-inch strips. Place on ungreased cookie sheet; spray tortilla strips with cooking spray. Bake 5 to 6 minutes or until golden brown and crunchy. Set aside to cool.
Meanwhile, in 3-quart nonstick saucepan, cook onion over medium heat 2 to 3 minutes or until soft. Add enchilada sauce and chicken broth. Heat to simmering. Add chicken. Simmer until onion is cooked through. Remove from heat; add cilantro. Serve with tortilla strips and garnishes.