Directions

1. Prepare your grill for two-zone cooking and build a medium-high fire.

   
   

2. Meanwhile, slice each potato lengthwise, then place the halves cut-side down on a cutting board. Use your knife to make 1/8th-inch slices, from the top to the bottom of the potato, without cutting all the way through. (If you nip off a few slices, no worries, just toss them in the skillet). Repeat with the remaining halves, then place the potatoes in a large bowl. Drizzle with enough olive oil to lightly coat, sprinkle with Thundering Longhorn seasoning, and use your hands to gently toss and coat the entire surface of the potatoes.
   

3. Slice a head of garlic in half horizontally.

   
   

4. When the coals are glowing red and covered with a fine gray ash, clean and oil the grill grates. Place a large, well-seasoned cast iron skillet over the fire to heat for 10 minutes. Then, carefully move the skillet to indirect heat. Pour a generous glug of olive oil into the hot skillet and swirl to coat. Being mindful of the hot pan, arrange the potatoes cut-side down in the skillet. Nestle in the two garlic halves, sprinkle butter over the pan and top with the sage sprigs. Close the grill and vent the grill for smoking and roast the potatoes, basting them with the sage butter every 10 or so minutes, until they are cooked through and crispy on top, about 45 minutes. Serve the potatoes and roasted garlic warm, straight from the skillet.