Filet salmon, de-bone and cut into 2-inch-wide strips.
For the dry brine, mix 4 cups demerara suger and ½ cup sea salt in a large bowl. Add salmon pieces a few at a time and cover with dry brine. Put coated pieces into zip-lock bags and into the fridge or cooler. Let them brine overnight (8 to 12 hours), turning once or twice to make sure they are completely covered.
When soaking is complete, remove salmon from bags and rinse with cold water. Set on trays, pat dry with paper towel, and let dry for 3 to 4 hours until surface has formed a pellicle (not sticky). A fan helps speed this process up.
In a small bowl mix equal parts of Disaronno liquor*, maple syrup, and brown sugar to form a thick paste.
Brush onto salmon pieces, sprinkle on a moderate amount of powdered cayenne pepper, and then put into smoker.
In my propane smoker, it takes about 2 to 3 hours at 120° – 140° F, and halfway though I brush more of the candy glaze on.
Notes
Other liquors like Jack Daniels and Fireball work as well.