1. Preheat grill to 250°F. Season your tri-tip very well with the savory coffee rub. 
2. Place tri-tip into the smoker and cook until it reaches an internal temperature of 125°F.
3. As your tri-tip gets close to the right internal temperature go ahead and get a cast iron skillet piping hot for searing with about 2 tablespoons of butter.
4. Once your tri-tip is up to temperature, remove from the grill and place into your cast iron adding a bit more coffee rub and searing each side for about a minute and a ½ basting as you go. 
5. Once seared, remove from skillet and let the tri-tip rest for about 10 minutes. 
6. Once rested, slice and enjoy!

Pro Tip! Tri-tips have two muscles running in different directions and you want to make sure you cut against the grain. But the tri-tip in half first, then slice each half against the grain.