Combine spices to make a rub. Reserve 1 T rub for later. Rub brisket with remaining rub. Let sit in large ziplock in fridge overnight.
Let brisket come to room temp for 45 min- 1 hr while smoker heats up to between 200-220 degrees.
Smoke brisket for 3 hours.
Wrap brisket in heavy duty foil, sprinkle with remaining 1 T rub and continue smoking until well-done and tender.
***Note: Briskets usually take 1 1/2 hours per pound in smoker. For slicing brisket thin, get internal temp to 180-190 degrees. For fall-apart tender, get internal temp to 195-205 degrees.
***Note: Trim brisket if fat is more than 1/4" thick. Make diagonal hatch marks across fat in a diamond pattern if necessary. Always smoke brisket with fat side up, the fat keeps the meat moist and juicy!