Combine all the brine ingredients in a large bowl or sealable plastic bag.
Mix and crush the ingredients with your hands, directly or through the bag, squeezing them to release the maximum flavor
Put the meat in the brine and let stand to absorb the flavors for at least 3 hours, and up to 14 hours. If brining for longer than 3 hours, refrigerate the pork.
Direct Grilling-Preheat the BBQ to medium-high. Combine all the ingredients for the baste except the parsley in a foil pan or heatproof pan and set on the side of the grill.
Drain the meat and dry with paper towels. Glisten with canola oil.
Put the meat on the well-oiled grill and cook for 10 minutes, moving the tenderloins regularly back and forth between the grill and the baste, turning them in the baste to moisturize them.
Transfer the meat to the baste and let rest for 5 minutes.
Return the pork to the grill and use the buddy system(use some of the pieces of meat to prop up others so you can caramelize and char the less-cooked sides) to brown the less-charred sides of each piece, holding it in place with the other tenderloins (you can check the temp with an instant-read thermometer if that is more comfortable; they should register 160F).
Meanwhile, add the chopped parsley to the baste and cook on the grill just until fragrant.
Add the pork tenderloins to the baste, turning to coat thoroughly. Pour the baste onto a cutting board and slice the tenderloins, turning to coat each slice.