Loving the flavor and look of Hasselback potatoes, I knew it wouldn't be long before I found myself grilling them again. This time around I went with a sweet potato rather than a russet since they're one of my favorite winter foods.
I kept the process exactly the same: slicing, washing, then jump starting the potato cooking process in the microwave. Then the partial cooked spuds were finished on the grill, where they fanned out and got crisp around the edges, while being soft and smooth on the inside.
While I thoroughly enjoyed my beautiful taters topped with rosemary and garlic, these do come with a warning from my wife who completely disagreed—finding them overly smoky and the garlic to be a conflicting flavor. Both of these issues are easily fixed—cook them in the oven and omit the garlic—but if I were making them for myself again, I wouldn't change a thing.
In a small bowl, mix together garlic, rosemary, and 1 teaspoon of olive oil. Set aside.
Cut off a thin slice of each potato lengthwise to create a even base for potato to rest on. Slice off ends of each potato. Rest potato between two chopsticks or wooden spoons to act as a stop for the knife and carefully cut vertical slits in each potato about every 1/8-inch.
Rinse potato under running water, fanning out to rinse inside of cut slits. Place potatoes on a plate and microwave at high for 4 minutes. Flip potatoes over and microwave again for an additional 4 minutes.
Light one chimney full of charcoal. When all the charcoal is lit and covered with gray ash, pour out and arrange the coals on one side of the charcoal grate. Set cooking grate in place, cover grill and allow to preheat for 5 minutes. Clean and oil the grilling grate. Brush potatoes with remaining olive oil and season with salt and pepper to taste. Place potatoes on cool side of grill, cover, and cook for 15 minutes.
Spread garlic and rosemary mixture over top of potatoes, cover, and continue to cook until soft in the center and crisp around the edges, 15-20 minutes more. Remove from grill, let cool for 5 minutes, then serve immediately while still warm.