Here is one version of povitica, that just might be one of the originals. I just had a taste of it, it is so delicious.
Ingredients are, ricotta cheese, but ideally it should be made from the milk of sheep rather than cow's milk,but I am sure regular ricotta, or farmers cheese should be good too, flour, sugar, baking powder, vanilla sugar, eggs, lemon rind, a little lemon juice is OK too, raisins are optional. Farmers cheese might need a bit more sugar tho.
In a bowl mix the cheese to a creamy consistency, if the cheese is too dry add a bit of milk. In a separate bowl beat the egg yolks and add sugar so it has time to be dissolved. Yet in a third bowl beat the egg whites until they form peaks.
To the cheese, add the flour and all the other ingredients with egg whites being last.
Pour into buttered and floured baking pan and bake at about 180 C, or 350 F, for about 45 min. Keep an eye and adjust temperature if needed.
The recipe I tried had 2 pounds (about 1 kilogram) of cheese with 2 eggs, 1 vanilla sugar, lemon rind from 1 small lemon, about 8 ounces of flour and the same amount of sugar, or roughly 1/4 of flour and sugar in comparison to the cheese.