Remoulades are pretty straight forward in terms of ingredients, it's the combining of them that makes the difference. I've always found a blender to work better than a food processor...although my little 3 cup Kitchenaid mini food processor does a damn good job too and is easier to clean that the big boy. I'm not a fan of adding capers or pickles to mine, but the cajun boys usually add BOTH! I make a batch the night before I use it.
OK, this is from memory...lol
3-4 stalks for green onions...use all of it!
a handful of fresh parsley leaves, no stalks...too bitter!
2-3 cloves of garlic run through a garlic press
(optional capers and/or sweet pickles)
Put those ingredients in a blender or small food processor until thoroughly combined...it almost looks like pesto without the pine nuts.
Then add...
1 cup Mayo...gotta be Hellmanns!
a nice medium drizzle of virgin olive oil
the juice from one lemon (half if you aren't a lemon fan)
2-3 tablespoons of Dijon mustard
3-4 turns of the pepper mill
salt to taste
Once completely mixed, put it in a bowl and refrigerate overnight or at least 3-4 hours.
Now, if you want to kick it up...subtract a little mayo and add a little horseradish and/or Tabasco sauce and try substituting hot mustard for dijon. Experiment with it.
I like mine a little more lemony on white fishes, so I add the juice of a whole lemon rather than a half of one. It isn't really rocket science as I change mine up to suit my mood and what I'm drizzling it on. Sometimes I add in some dry mustard if it's a hearty fish dish...salmon, swordfish, etc. If I'm using it on beef I'll add a little worcestershire sauce, dry mustard, horseradish, and a tiny splash of red wine vinegar. To freshen it up for shrimp or scallops, some people use celery (or the leaves only) in the first mixing, but in my opinion, you have to strip the veins out before adding it in because it roughens up the smooth consistency to me...but it does add a nice herbal flavor....fresh basil works well as a 'freshening/herbal agent' too.
The one thing I like on mellow white fishes is I add in one cube of Knorrs shrimp bouillon, it kinda soft and comes in a foil wrapper...this stuff is so hard to find but worth the effort to track down. It's great for making ANYTHING you prepare (white cream sauces, red clam sauce, gumbo) taste a little more seafood-y...awesome stuff!
Once you do it a few times, you can throw it together in 10-15 minutes. Good luck.