- 1¾ pounds baking potatoes, peeled
- 3 plump garlic cloves
- 2 teaspoons salt, or more to taste
- 1 bay leaf
- ¼ cup butter, at room temperature
- ¾ cup buttermilk, at room temperature
- 1½ tablespoons prepared horseradish
- 1½ teaspoons minced fresh thyme or ¾ teaspoon dried thyme leaves
- 8 ounces mozzarella cheese, grated
- Place the potatoes in a heavy pan and cover them with water by at least 1 inch. Add the garlic, 2 teaspoons of salt, and the bay leaf Cook the potatoes over medium heat until they are tender, about 25 to 35 minutes depending on their size. Drain the potatoes, reserving the garlic.
- When the potatoes are cool enough to handle, rice or mash them and the garlic back into their original pan. Put the pan over low heat and stir the potatoes continuously for 1 to 2 minutes to dry them out thoroughly.
- Add the butter, 2 tablespoons at a time, stirring well after each addition. Pour in the buttermilk, about ¼ cup at a time, while continuing to stir. Add the horseradish, thyme, and all but 3 tablespoons of the cheese. Taste and season with more salt if you wish. Spoon the mixture into an greased smokeproof baking dish and sprinkle with the remaining cheese. (The potatoes can be made to this point 1 day in advance. Return to room temperature before proceeding and add 5 or 10 minutes to the smoking time.)
- Bring your smoker to its appropriate cooking temperature.
- Transfer the potatoes to the smoker and cook them until the cheese has melted and the potatoes are well perfumed with smoke, about 25 to 35 minutes at a temperature of 225° F to 250° F. Serve hot.