Remove silver skin and extraneous fat from meaty side of picanha.
Cut crosshatch pattern into fat cap with about 1-inch between each cut
Place meat into foil pan for seasoning.
Pour about 2 TBS of Worcestershire sauce onto fat cap followed by 1.5 TBS of Jeff's Texas style rub and 1 teaspoon coarse kosher salt.
Flip meat to fat cap DOWN.
Once again , Pour about 2 TBS of Worcestershire sauce followed by 1.5 TBS of Jeff's Texas style rub and 1 teaspoon coarse kosher salt.
Place the pan of meat into the fridge for at least 2 hours. Overnight is best.
Make the chimichurri while the meat is in the fridge.
Set up cooker according to manufacturers instructions and when it's ready, place the meat fat cap DOWN onto the grate.
Replace the bars and lid and let it cook until it reaches 110°F (43°C) in the thickest part.
Crank up the heat by cracking open the lid about 1 inch and opening the air vent at the very bottom of the barrel.
When the picanha reaches 130°F (54°C) in the thickest part, remove it from the cooker and let it rest under foil for 15 minutes.
Slice into pieces that are ¾ inch thick and serve immediately with room temperature chimichurri sauce.
Make Chimichurri
Add all chimichurri ingredients except for the salt and greens into a large bowl and stir together.
Chop parsley and cilantro and add to the bowl (coarse chop is best). Stir well to combine.
Salt to taste.
Place chimichurri into fridge for several hours to allow the flavors to combine.
Notes
You can use another grill or smoker for this picanha but be sure to cook to temperature rather than time.Be sure to stop the cooking process early and find a way to crisp the fat cap under super high heat.When the meat reaches 130°F (54°C), it has reached a perfect medium rare.