Begin by preheating your grill to 350°F, keeping the lid shut. As the grill heats up, take one russet potato and place it in a medium-sized bowl. Poke the potato several times with a fork, ensuring to make small holes across its surface. Drizzle a bit of neutral oil over the potato, coating it evenly. Repeat this process for the remaining potatoes.
Next, fill another medium bowl with enough salt to cover its bottom completely. Roll each oiled potato in the salt, ensuring they receive a light and even layer of salt all around. Once coated, transfer each potato to a microwave-safe plate or bowl.
Place the prepared potatoes in the microwave and cook them all together on high power for 4 minutes. After microwaving, carefully remove the potatoes and wrap each one tightly in two layers of aluminum foil.
Place the foil-wrapped potatoes directly onto the grill grates. Close the grill lid and cook for 30 to 40 minutes, keeping the lid shut to maintain consistent heat. Note: Avoid opening the grill lid frequently, as this will extend the cooking time.
After about 30 minutes, begin testing the potatoes for doneness. Carefully unwrap one potato slightly and use a fork or skewer to pierce through the skin. The potato is ready when the fork or skewer goes through effortlessly without resistance. Once done, remove all the potatoes from the grill.
Unwrap the potatoes and discard the foil. To serve, slice each potato lengthwise down the center and gently press the ends together to open up the middle. Fluff the soft interior with a fork, and add your favorite toppings immediately. Enjoy!