Peel the sweet potato, boil it, and mash it.
Add sugar, butter, and salt to the mashed sweet potato and mix well.
Sift together the flour, baking powder, and salt.
Add the flour mixture, milk, and eggs to the sweet potato dough and knead well.
Divide the dough into appropriate portions and shape into balls.
Place mozzarella cheese in the center of each dough ball and wrap it up.
Heat cooking oil in a pan and cook the bread over medium-low heat until golden brown.