Make the rub: Chop the fresh herbs and mix with the cure ingredients.
Cure the meat: Cover the tri-tip on all surfaces with the cure. I used a very thick coating and cured it for 24 hours. Cure it in the fridge for desired time.
Discard the cure: Scrape off the cure before smoking. I left some cure on the meat for pockets of flavor. If you prefer, you can rinse the cure off. Pat the tri-tip dry with paper towels.
Smoke the meat: I smoked this for 90 minutes at 225°F for medium rare. A larger tri-tip will require a longer smoke time. To reach 125°F, remove the tri-tip at 115°F. During the next steps, it will continue to cook and carry up to 125°F.
Ignite the grill: About 15 minutes before the tri-tip is done, ignite the gas grill. If you are using charcoal or wood, heat the grill 30 minutes before the tri-tip is done.
Sear the steak: Remove the tri-tip and place it on the hot grill to sear the outside for color and char.
Let it rest: After the tri-tip is marked on the grill, wrap it in aluminum foil. Then place it in a ziptop baggie, squeezing out the air. Place that baggie inside another and squeeze out the air before you seal it. Wrap that package in several kitchen towels to keep the heat while it rests for at least 30 minutes.