In a medium saucepan, bring the chicken breast and broth to a boil. Lower the heat; cover and simmer until the chicken is cooked. Remove the chicken; let cool. Shred the meat, reserve.
Whisk the curry paste, into the broth, add soy sauce and return to a simmer over the medium high heat. Add the noodles and bell pepper and cook until noodles are just tender, about 3 min. Stir in the chicken.
Ladle the soup into bowls and top with the scallions and cilantro leaves. Serve with the lime wedges.