Prep Potatoes: Preheat oven to 350°F (176°C). Cut sweet potato crosswise into round discs, about ¼ inch thick. Brush each side with oil and arrange on a parchment-lined baking sheet in a single layer. Sprinkle with salt and pepper.
Bake Potatoes: Bake for 20 minutes, or until fork-tender.
Goat Cheese: Meanwhile, whisk together goat cheese and milk until smooth.
Assemble: Let potatoes cool slightly, then top each with a dollop of whipped goat cheese, a spoonful of cranberry sauce, and a sprinkle of pepitas.