Cedar Planked Salmon

I'm working on a recipe, and I'm torn between two choices.

The dish is a cedar planked salmon with a fried onion crust (ok, I'm not
making these, using the canned variety.)

I'm entered this twice in contests and have 2 3rd places...I'm trying to kick
it up a notch. I've been making this with the salmon coated with a honey
dijon mustard sauce, crusted with the onions, and then a white wine/lemon
reduction sauce to cut the richness. It's pretty dang good.

Now I'm thinking about two other options.....in between the salmon
and the onion crust (which will include grated parmesan and herbs)
I'm thinking about using some sort of creamy mixture, or a some sort
of relishy mixture.

My thoughts are:

for the cream type, a mayonnaise or mustard or sour cream base
with some flavoring agents, including some with texture. I'm not
feeling good about fruity flavors here, except for lemon.


for the relishy/pesto type, I'm thinking of a bright but thick
sauce with enough zing to compliment the fish and balance the
richness of the topping...


I'm interested in trying some tarragon or balsamic vinegar in either
case, or perhaps a more creamy Imperial style sauce would work..

any comments or suggestions would be greatly appreciated!

Most important, I stink at sauces! Especially cooking on site...
did decent with a buerre blanc, but had trouble getting it thick enough.

wow, thanks for all the responses...

Bug, the horseradish sounds like the perfect sharpness, I'm gonna
play around with that.

Phatch, you're right, the amateur contests are judged by amateur
judges....local tv weathermen, etc. While organizations like the
Kansas City Barbecue Society train judges, the salmon is being
entered into a Friday night event called Anything Butt Pork, which
means anything except desserts and barbecue. The judges here
will be less trained than the judges on Saturday for the bbq categories.

To win on Friday night, you need a dish that doesn't offend, and has
a wow factor. Some of my teammates love cleaned jalapeno peppers
stuffed with cream cheese and pulled pork barbecue, wrapped in bacon
and grilled indirect. They are addictive, but polarizing. To thank my
crew I let them enter that in comp last April. The results were just
as I thought. People either loved em or refused to eat them because
they were jalapenos. We finished middle of the pack.

Salmon is not my favorite choice to make simply because some folks
don't like fish. This treatment wins many over, but that is the exact reason
why I'm not highlighting the fish. BTW, my monger feels pretty sure
he can get me fresh Faroe Island salmon, which I but from him and
take home and eat raw, sometimes with a little wasabi/soy. It's outstanding.

Adam, I'm cooking high heat on a charcoal grill, starting direct and going
indirect....it doesn't take long. I'm using a very light rub of salt and pepper
with lemon zest....most of the flavor is in the next step, the honey dijon
mix....that's what I'm looking to improve on.

I do not soak my plank, but I do oil the side the fish goes on. And I use
canned onions for convenience, and probably because I couldn't do better
than the canned ones. I'm just a grill guy, and the judges aren't gourmet
for the most part.