01 - Roast or steam the Korean sweet potato until completely tender. Allow to cool, remove skin, and cut into 1-inch chunks.
02 - Combine sweet potato chunks, milk, sweetener (if using), and vanilla extract in a blender. Process until completely smooth and creamy, approximately 1-2 minutes.
03 - Transfer blended mixture to a saucepan. Warm over medium-low heat, stirring frequently, until steaming hot but not boiling.
04 - Pour hot latte into mugs. Dust with ground cinnamon or nutmeg if desired. Serve immediately while hot.