Combine first 6 ingredients in a heavy-duty, zip-top plastic bag; add chicken. Seal bag, and shake until chicken is well coated. Marinate in refrigerator 1 hour, turning occasionally.
Remove chicken from marinade, reserving marinade. Place marinade in a small saucepan; add broth, and bring to a boil. Remove from heat, and set aside.
Place peppers and onion in a 13- x 9- x 2-inch baking dish coated with cooking spray. Bake, uncovered, at 400° for 10 minutes. Stir in chicken. Pour marinade mixture over chicken and vegetables. Bake 15 to 18 minutes or until chicken is done.
Wrap tortillas in aluminum foil. Bake at 325° for 15 minutes.
Spoon chicken and vegetables evenly down centers of tortillas, using a slotted spoon; roll up tortillas. Top each with 1/4 cup chopped tomato and 1 tablespoon sour cream.