Prepare the ingredients: Wash the sweet potato thoroughly, peel it, and cut into 2cm chunks (uniform size ensures even cooking). Rinse the millet gently with water 2 times—just to remove surface dust, do not over-rub to avoid losing nutrients.

Combine in a pot: Place the sweet potato chunks and rinsed millet into a pot (a clay pot works best for richer flavor and creamier texture, but a regular pot is fine too). Stir gently to prevent millet from sticking to the bottom.

Add water and bring to a boil: Pour in the water, ensuring it covers the ingredients by 3-4cm. Turn the heat to high and bring the mixture to a rolling boil. Skim off any foam on the surface for a smoother congee.

Simmer slowly: Reduce the heat to the lowest setting, cover the pot with a lid (leave a small gap to prevent overflow), and simmer for 30-40 minutes. Stir the congee every 10 minutes to avoid sticking and burning.

Season and serve: Cook until the millet blooms, the sweet potato turns tender and melts into the congee, and a layer of creamy film (millet oil) forms on the surface. Add a pinch of salt if desired, stir well, then turn off the heat. Let it rest, covered, for 5 minutes to absorb flavors and thicken further.

Serve with sides: Enjoy the congee on its own, or pair it with steamed buns, shaobing (Chinese sesame flatbread), dumplings, or preserved meat for a hearty breakfast.