Steps
1. Cook the pasta according to package instructions until al dente. Drain and rinse under cold water to cool.
2. In a bowl, combine mayonnaise, mustard, salt, and pepper to make the dressing.
3. Add the cooled pasta, diced chicken, cherry tomatoes, cucumber, and parsley to the bowl.
4. Toss everything gently until well coated with the dressing.
5. Adjust seasoning if needed and serve chilled or at room temperature.