In a pot over medium heat, bring the quart of water to a soft boil.
Once the water is boiling, add the kosher salt and brown sugar. Simmer for 20 minutes, or until the salt and sugar are fully dissolved.
Transfer the brine to the fridge to cool for 30 minutes.
Place your salmon in a plastic or glass container with the skin facing upward. Pour the cooled brine mixture over the top of the salmon, cover, and put back in the fridge for at least 4 hours (8 hours is recommended).
After the salmon has brined for at least 4 hours, remove it from the brine and rinse it under cold water to remove any excess salt.
Lay the salmon on a wire rack or baking rack and let it sit at room temperature for 2 hours to dry out. You will notice a shiny, skin-like pellicle form on the outside of the salmon during the drying process.
Preheat your smoker to 175°F.
Combine all of the dry rub ingredients in a bowl, then season each salmon filet with the rub mixture.
Transfer the seasoned salmon filets back to the wire rack with the skin facing down.
Place your salmon on the smoker and let it smoke for 2 to 3 hours, or until the internal temperature reaches 150°F. Start checking the temperature of the salmon at the 2 hour mark.
Once the salmon reaches an internal temperature of 150°F, remove the rack from the smoker and let it cool at room temperature for 1 hour.
Store salmon in the fridge until ready to serve – up to 1 week.