- Prepare macaroni in lightly salted water according to package directions. Set aside.
- In a large bowl combine the macaroni, celery, cucumber, green onion, parsley, diced ham, tomato, hard-boiled eggs, if using, and relish. Set aside.
- In a small bowl or blender, whisk together the mayonnaise, mustard, sugar, vinegar, sour cream or Greek yogurt, salt and pepper. Pour dressing over salad and stir to combine. Season salad with salt and pepper to taste. Refrigerate for at least one hour.
- If making the night before or more than one hour before serving, pour half of the dressing over the salad and mix well. Refrigerate and just before serving, add the rest of the dressing and mix well again.