Cook the sweet potato with the skin on in boiling water until tender. Drain, remove the skin and mash with a fork until it forms a puree.
Beat the eggs slightly and place together with the potato, mix, add the butter, sugar, salt, condensed milk, grated coconut and mix again. Finally, add the baking powder, mixing gently without beating.
Mix everything gently, with movements from bottom to top, until you form a very homogeneous mass.
Place in a rectangular shape 30cm long and 20cm wide, greased and infarinhada.
Bake in a preheated oven at 180° for about 40 minutes or until lightly browned.
Remove from the oven, let it cool and sprinkle the sugar mixed with cinnamon.