Cut the cauliflower into florets, place the florets in a steamer, and steam them for 7 to 8 minutes, until the cauliflower is softened but still retains some texture.
Remove the cauliflower and allow it to cool completely, then place the cooled cauliflower into a clean bowl.
In a separate bowl, combine together the mayonnaise, lemon, mustard, fresh dill, chives, and red onion.
Add that mixture to the cauliflower and mix everything thoroughly.
Finely chop the hard-boiled eggs and then add this, along with the chopped pickles, to the bowl with the cauliflower. Gently mix everything together (and top with a few more chopped herbs if desired). Add salt and pepper to taste, if desired.