Bring a large pot of salted water to a boil.

Add the cauliflower florets and cook until al dente, about 6 minutes.

Drain and cool.

In a mixing bowl, combine the cooked cauliflower, diced hard-boiled eggs, diced ham, grated carrot, and thinly sliced green onions.

In a separate small bowl, whisk together the mayonnaise, sour cream, sweet relish, and Dijon mustard.

Pour the dressing over the cauliflower mixture and gently stir until everything is well coated.

Season the salad with salt and pepper to taste.

Refrigerate the salad for at least 30 minutes before serving.

Serve chilled, garnished with chopped parsley if desired.