Pull the tri tip out of the refrigerator 45 to 60 minutes before you plan to cook. Letting it come closer to room temperature ensures more even cooking from edge to center. Pat it completely dry with paper towels - moisture is the enemy of a good bark and dry surface means better crust development on the fire.

Mix together the kosher salt, black pepper, garlic powder, onion powder, smoked paprika, dried oregano, and cayenne in a small bowl to create your Santa Maria rub. Coat the tri tip all over with a light layer of olive oil, then apply the rub generously on all sides, pressing it into the meat with your hands so it adheres. Do not be shy - this is a thick roast and it needs that seasoning to penetrate.

Fire up the grill for a two-zone setup. For charcoal, bank your lit coals to one side of the grill and add your wood chunks directly on top of the coals. Target a grill temp of 250 to 275 degrees Fahrenheit on the indirect side where you will start the cook. For a smoker, get your firebox burning clean with a thin blue smoke before you load the meat. Avoid thick white billowy smoke - it will make the beef taste bitter.

Place the tri tip fat cap side up on the indirect heat zone of your grill or smoker. Close the lid and let it cook low and slow, maintaining that 250 to 275 degree Fahrenheit range. The fat on top will slowly render down through the meat, basting it from the inside. Do not open the lid more than once every 20 to 25 minutes - heat and smoke are your friends here, and every peek means lost time and temp.

Monitor the internal temp with your instant read thermometer. You are targeting an internal temp of 110 to 115 degrees Fahrenheit before the sear - this is your cue to get ready for the next phase. At this point the bark should be forming nicely, darkening to a deep reddish-brown with visible seasoning crust on the surface. If you see a smoke ring forming on the edges, you are doing everything right.

Once the tri tip hits 110 to 115 degrees Fahrenheit internal, pull it off the indirect side and crank your coals or open your vents to bring the direct heat zone up to 450 to 500 degrees Fahrenheit. Sear the tri tip directly over the hot coals for 2 to 3 minutes per side, flipping once, until you get a deep caramelized crust on both faces. Watch for flare-ups from the fat dripping - use your tongs to move the meat slightly if flames get aggressive.

Pull the tri tip off the grill when the internal temp reads 130 to 132 degrees Fahrenheit for a perfect medium-rare finish. Carryover cooking will bring it up to 135 degrees Fahrenheit during the rest. Place it on a cutting board and tent loosely with foil - do not wrap it tight or you will steam off that beautiful bark. Rest the meat for a minimum of 10 to 15 minutes. This is not optional. If you slice too early you will lose half your juices onto the cutting board.

Slicing tri tip correctly is just as important as cooking it right. The grain of a tri tip changes direction roughly in the middle of the roast, so study the meat before you cut. Slice against the grain in thin cuts about a quarter inch thick. Cut one half of the roast, then rotate the other half 90 degrees and slice against that grain direction. Serve immediately and watch it disappear.