Combine the chopped onion, apple and butter and cook in a skillet until soft. Add the chicken broth and mustard. Once that is well mixed, add the chicken.
Cover and poach over low heat until cooked thoroughly, about 15 minutes. Add pepper and dill to season.
Nutrition facts per serving: Calories 494, Protein 38 grams, Fat 16 grams, Carbohydrate 8 grams, Fiber 1 gram, Sodium 628 mg