Prepare a Brine

• Meat is prone to drying out when you cook it over an open flame, but you can saturate the pork loin with additional moisture by brining it. The primary ingredients in a brine are water, salt and brown sugar. Add 1/4 cup of table salt and 1/4 cup of brown sugar for every 2 cups of water. Prepare enough brine to submerge all the meat. You can substitute an equal amount of another liquid, such as apple cider or beer, for some of the water. Season the mixture to taste with herbs and spices. Thyme, sage, fennel seeds, rosemary, bay leaves and pepper-based spices complement pork.

Soak and Season the Pork

• Put the pork and brine in a resealable plastic bag, and store it in the refrigerator while it soaks for 4 to 12 hours. Rinse the meat in cool running water after removing it from the bag, and discard the remaining brine. Apply a dry rub to the pork loin to further season it, if desired. While the pork absorbs flavor from the brine, you should season the meat again if you want the herbs or spices to be robust. Put the pork loin on a plate or platter, cover it with plastic wrap and let it rest at room temperature for 1 hour before grilling it.

Create Zones in Your Grill

• Create hot and cool zones in your grill so that you can alternate between cooking the pork with direct and indirect heat. By searing the meat over direct high heat, you seal moisture into the meat and create a savory, caramelized surface. Then you slow-roast the pork with indirect heat to cook the meat through without robbing it of moisture. To create zones in a charcoal grill, bank the briquettes on one side of the grill before lighting it. In a gas grill, turn off half the burners after you preheat the entire grill.

Sear Then Slow-Roast the Pork

• Lay the pork loin meat-side-down directly over the flame, then cover the grill. Sear the surface of the meat, flip it with tongs, then sear the reverse side. Transfer the browned pork loin to the cool zone, and cover the grill. Use a meat thermometer to assess the pork’s done-ness. A bone-in pork loin should roast about 20 minutes per pound.

Testing and Resting

• Use a meat thermometer to determine precisely when the pork is done. Insert the thermometer into the center of the meat away from bone. Remove the pork from the grill when the internal temperature is 140 degrees Fahrenheit. Pork must reach 145 F to be safe to eat, but ambient heat continues cooking the pork after you remove it from the grill. The residual heat raises the pork’s temperature about 5 degrees before it begins to cool. Cover the pork with aluminum foil and rest it for 3 to 15 minutes. Resting the meat allows the juices to thicken, preventing them from running excessively when you slice the pork.