This is my go-to for hot smoking salmon. The recipe was tuned up before I actually had a smoker so it's designed for a gas grill.
This is the evolution of another salmon recipe I've used for years.
Cut your skinless salmon fillets into 1" strips, across the grain.
In a large plastic or glass bowl mix 1 part pickling or kosher salt with 2 parts brown sugar.
In a large glass or plastic container put a 1/4" layer of the mixed cure followed by a layer of salmon strips. Cover with cure and repeat layering until the container is near full. Put a lid on the container and let it sit in the fridge for 4-6 hours, mixing it up every hour or so. (The cure will turn into a liquid). The fillets are done once they take on a firm texture and the edges become translucent.
Remove all the fish and rinse it thoroughly with cold water. Take the time to rinse for a good 5-10 minutes, making sure to rinse every individual piece a few times. If you don't, it'll end up too salty. Let it dry in a strainer for 5-10 minutes.
Wash out the container and put all of your clean salmon back into it. This time cover the fish with 1 part soy sauce to 3 parts pure maple syrup. At the same time, put 3-4 cups of wood chips/shavings (I use Alder) in a separate bowl of water and let them soak as well. Let the salmon sit in the fridge for at least 12hrs, stirring and flipping a few times over the course of it.
After 12 hrs don't rinse the salmon off, but drain it and let it sit on a drying rack until it gets tacky to the touch. Scorch your bbq grill, clean it and rub it down with olive oil on a paper towel. Set your bbq to it's lowest setting. If you have a side searing station in the main grill, perfect. You're looking for 170-180 degrees.
Lay the salmon strips across the grill pattern (if you lay them with the grill they'll be tougher to move without breaking once the salmon warms up and gets soft), and brush every strip with 100% maple syrup, just one good coating.
Throw a few cups of soaked wood chips into a small pie plate and put it over the side of your grill that is on (again, the searing station works perfect) I put through two cycles of wood chips, over a half hour or so and then that's it for smoke. Pay close attention to the wood chips because you're gonna want to get them out of there as soon as they've done there burn, even a bit before every last chip is black. If you leave the chips in for too long you'll pick up that acrid, bitter smoke flavor.
Once the smoking is done let the fish sit in the bbq @ 180ish for another 2-3 hours. At this point you can remove the salmon and package it as is, or you can do the next step which my wife and I agree just make this recipe what it is.
Once our fish is done in the bbq I go out and open the lid and crank the bbq onto high. I'll stand out there with a table next to me with a cooling rack on it and just monitor/turn the salmon for the high temp part. I try to get it so that every piece of fish has a decent amount of slightly charred meat. If you do this right quickly, you'll mostly be charring the syrup that's on the outside which I find REALLY elevates the flavor.
Once they've all got a splash of "burnt" on them I let them cool outside on the rack until they're cool enough to vacuum seal.
The salmon meat will be quite flaky and weak when you're charring it so be prepared to be fast but gentle with your tongs. It's going to break into smaller pieces no matter what you do, you're just trying not to destroy it so that it falls apart completely and drops through your bbq grate. It really firms up nicely once it's totally cooled off.
I'll add some pictures the next time I open a package. I'm telling you, once you have a chunk of this sweet/smokey salmon you're going to have a hard time not eating the entire package. That's why we package it in reasonably small portions. Otherwise I make a pig of myself.