In a large bowl, mix flour, salt and yeast. Add sweet potato mixture and egg and knead to make a soft dough. You can do this by hand or using a food processor. If the dough is too soft, add some more flour. If it is too stiff, add more milk.
Divide the dough into 16 pieces. Roll each piece and put in an oiled baking dish (I used 26 cm / 10" round pan). Cover and place in the oven for another 10-15 minutes.