Pat the salmon fillet dry and remove any pin bones using tweezers.

In a bowl, mix together brown sugar, kosher salt, black pepper, garlic powder, and cayenne pepper to create the rub.

Generously rub the spice mixture over both sides of the salmon fillet, ensuring an even coating. Place the fillet in a baking tray, cover with plastic wrap, and refrigerate for 2 hours to let the flavors mingle.

Fire up your Bradley smoker and set it to a temperature of around 225°F (110°C). Fill the smoker's tray with your choice of wood chips – apple, cherry, hickory, or mesquite – and let them start smokin'.

Place the well-seasoned salmon fillet on the smoker racks and close the lid. Let it smoke away, absorbing those gorgeous flavors for 2-4 hours. Keep an eye on the smoke levels and add wood chips as needed to maintain that smoky goodness.

After your salmon has soaked up the smoky magic, use a fork to gently test its doneness. It should flake easily and have that irresistible smoky aroma.

Once perfectly smoked, remove the fillet from the smoker and let it rest for a few minutes. Then, slice it into beautiful portions.