Preheat your oven to 400°F (200°C).

Peel and slice the sweet potatoes into thin medallions, about 1/8 inch thick. Arrange the slices in a greased 9x13 inch baking dish, ensuring they overlap slightly.

In a medium saucepan, melt 4 tablespoons of unsalted butter over medium heat. Add 1/2 cup brown sugar, 1/2 cup water, 1 teaspoon ground cinnamon, 1/4 teaspoon ground cloves, 1/4 teaspoon ground nutmeg, and a pinch of salt. Stir until smooth and dissolved, about 3-4 minutes.

Using a basting brush or spoon, coat the sweet potato medallions with approximately 3/4 of the warm sauce.

Cover the baking dish with aluminum foil and bake for 45-50 minutes, or until fork-tender.

Remove the foil, drizzle the remaining sauce over the sweet potatoes, then sprinkle with 1/2 cup of chopped pecans and 1-2 cups of mini marshmallows. Broil on high for 1-2 minutes until golden brown.

Allow to rest for 10-15 minutes before serving.