Alright - All of the above comments are great, season the salmon any way you like (unless it involves slathering mayo all over it).
First, starting with the right type of salmon helps - Atlantic has very little fat in it. Pacific and Alaskan salmon has much more fat - We know that fat is your friend...
THE KEY to incredible salmon is this (keep an open mind now)...
Koshering.
A few of the things that koshering will do:
1) most salmon you get in the super market these days is a bit mushy or mealy - koshering firms up the outter layer of flesh and gives a great flakey presentation.
2) anyone that has ever cooked salmon knows that the thing usually looks ugly as fark once it's done cooking - you have juice that's weeped out all over the place and then semi solidified on top, the meat is a horrible color (to me it looks exactly like
ET's skin when he gets sick).
When you kosher, the outter layer of flesh is sealed up and no longer weeps all of this juice out, that allows the flesh to brown up and looks amazing.
3) Salmon dries out pretty easy since there is not much collegen or fat present to retain moisture. the koshering retains the juices by sealing the outter flesh. I have literally cut into a fillet after cooking this way and had juice squirt out! Tell me any time that's happened for you! Rarely if ever I would bet.
How to:
Take a skin on fillet and lay it skin side down in a shallow pan that will allow for the full length. Next completely cover the
flesh side with rock salt (I use mortons ice cream salt, do not use any regular salt i.e. kosher, table or sea salt, these dislove too quickly and will impart a salty tasting fish). You want absolutely every square inch covered,
no pink showing at all. Lightly press/pat the salt into the meat so that you have good contact.
Let that sit for about 20 min, no more than 30 min.
You will notice that some water will begin to puddle up in the bottom of the dish - You might be tempted
to think that you're drying out the fish by doing this,
that would be a mistake. In fact, you're literally sealing up the outside of the flesh so that during the cook no moisture will be lost.
After your 20-30 min kosher, rinse off all the salt under cold water and gently rub the flesh to remove all salt residue, I usually rinse for about 3 min or so. Pat dry with paper towels and pick off any scales that stuck to the flesh.
You'll probably notice that the flesh feels different after the kosher, it's no longer as slimey and it has a firmer texture on the outside.
Cooking:
I plank my salmon, it cooks more evenly and does not require turning. You can also take the plank directly to the serving table without it falling apart.
Many folks like cedar planks, meh... they're ok... the cedar flavor IMO overpowers the simple flavor of the fish and becomes distracting. The only time I use cedar is if I have time let it soak in a bucket of water for
months to draw out the strong tannins that give off the strong cedar flavor. I prefer alder, maple or even oak.
Soak the plank in water for at least an hour (use a 5 gal bucket and set a weight on top to hold the plank under water)
15 min before you're ready to cook, put the plank into the heated cooker and let it preheat.
Rub a little olive oil on the top of it or spray some pam just before you put the fish on it, it'll help with clean up if you decide to use the plank again.
Lay the fillet on it and lightly season with any of the flavors you like the most, I would recommend using a lighter amount of salt as the koshering does impart a small amount of salt to the meat (far less than you'd think though, remember, this fish has lived in salt water all it's life and doesn't taste salty on it's own)
I typically grill it with this method, but if you're using the FEC 300 - 350 should be fine, depending on the thickness of the fillet, it takes about 45 min (little longer since the plank is slower to transfer heat to the underside of the fillet than what a grate would).
Cook it to 140 in the thickest part and remove. Not 141, not 142... 140.
A rest is not necessary - dig in!
Additional options to try - add a little sugar, brown sugar, garlic or herbs & spices to the rock salt - this will draw in some of those flavors during the koshering process.
As bizaar as this sounds, once you've tried it you'll never do salmon without it!