In a large, non-reactive container, mix all ingredients (except salmon fillets) until dissolved. Add fillets, making sure the are covered with brine. Cover the container and marinate overnight in the refrigerator.
The next day, remove fillets from the brine, pat dry with paper towels, and arrange on racks.
Smoke salmon according to your smoker’s instruction manual. We like to use a combination of hickory and alder chips. Check fish frequently for doneness.
Cook's Note: Do not reuse brine, always make a fresh batch.