In a small bowl, stir ½ teaspoons sugar, ¼ teaspoon flour, and the yeast into 2 tablespoons warm water and cover with plastic wrap. Allow standing for 5 minutes
To Make the Dough
In a medium saucepan, heat the milk to just below boiling (about 180°F/82°C), stirring constantly so that a film does not form on the top of the milk. You want it hot enough to scald you, but not boiling.
Allow cooling slightly, until it is about 110°F/43°C.
In a large bowl, mix the scalded milk, 3 tablespoons (43 gm/ 1 ½ oz) sugar, and the salt until combined. Add the beaten egg, yeast mixture, melted butter, and ½ cup (120 ml/70 gm/2 ½ oz) of flour.￼
Blend thoroughly and slowly add remaining flour, mixing well until the dough starts to clean the bowl.
Turn dough out onto a floured surface and knead, gradually adding flour a little at a time, until smooth and does not stick.
Place dough in a lightly oiled bowl, cover loosely with a layer of plastic wrap and then a kitchen towel and let rise an hour and a half in a warm place, until doubled in size.
To Make the Filling
In a large bowl mix together the ground walnuts, sugar, cinnamon, and cocoa.
Heat the milk and butter to boiling.
Pour the liquid over the nut/sugar mixture.
Add the egg and vanilla and mix thoroughly.
Allow standing at room temperature until ready to be spread on the dough. If the mixture thickens, add a small amount of warm milk.
To Roll and Assemble the Dough
Spread a clean sheet or cloth over your entire table so that it is covered.
Sprinkle with a couple of tablespoons to a handful of flour (use flour sparingly)
Place the dough on the sheet and roll the dough out with a rolling pin, starting in the middle and working your way out, until it measures roughly 10-12 inches (251⁄2 cm by 301⁄2 cm) in diameter. Spoon 1 to 1.5 teaspoons (5ml to 7 1⁄2 ml/4 gm to 7 gm) of melted butter on top.
Using the tops of your hands, stretch the dough out from the center until the dough is thin and uniformly opaque. You can also use your rolling pin, if you prefer. As you work, continually pick up the dough from the table, not only to help in stretching it out, but also to make sure that it isn’t sticking.
When you think the dough is thin enough, try to get it a little thinner. It should be so thin that you can see the color and perhaps the pattern of the sheet underneath.
Spoon filling (see below for recipe) evenly over dough until covered.
Lift the edge of the cloth and gently roll the dough like a jelly roll.
Once the dough is rolled up into a rope, gently lift it up and place it into a greased loaf pan in the shape of a “U”, with the ends meeting in the middle. You want to coil the dough around itself, as this will give the dough its characteristic look when sliced.
Brush the top of the loaf with a mixture of 2 tablespoons (30 ml) of cold STRONG coffee and 1 ½ teaspoon of sugar. If you prefer, you can also use egg whites in place of this.
Cover the pan lightly will plastic wrap and allow to rest for approximately 15 minutes.
Preheat oven to moderate 350°F/180°C/gas mark 4.
Remove plastic wrap from dough and place into the preheated oven and bake for approximately 15 minutes. Turn down the oven temperature to slow 300°F/150°C/gas mark 2 and bake for an additional 45 minutes, or until done.
Remove bread from the oven and brush with melted butter. Check the bread every 30 minutes to ensure that the bread is not getting too brown. You may cover the loaves with a sheet of aluminum foil if you need to.
Remove from the oven and allow to cool on a wire rack for 20-30 minutes. It is recommended that the best way to cut Povitica loaves into slices is by turning the loaf upside down and slicing with a serrated knife.