Prepare the walnut filling by combining finely ground walnuts, eggs, milk, sugar, honey, and cinnamon in a heavy saucepan.

Cook the filling over low heat, stirring frequently, until it thickens (about 30 minutes).

Set the filling aside to cool.

Prepare the dough by dissolving fresh yeast cake with warm water and a little sugar in a heated bowl.

Let the yeast mixture sit in a warm place until foamy (about 5 minutes).

In a separate bowl, combine melted butter, sugar, and salt.

Add boiling water to the butter mixture and stir until lukewarm.

Add the lukewarm mixture to the yeast mixture.

Stir in beaten eggs and gradually add flour.

Turn the dough out onto a floured board and knead for about 5 minutes.

Place the dough in a greased bowl, cover, and let it rise in a warm place until doubled in bulk.

Cover a work table with a large cotton dish towel or cloth and sprinkle it lightly with flour.

Place the dough in the center of the floured cloth and roll it out as thin as possible, maintaining a square or rectangle shape.

Spread the prepared walnut filling evenly over the rolled-out dough.

Sprinkle raisins over the filling.

Roll up the povitica like a jelly roll, using the cloth to lift and roll the dough.

Place the rolled povitica in a large greased baking pan, forming it into an "S" shape.

Tuck in the ends and flatten it slightly. Alternatively, cut it in half and bake in angel food cake pans or bread pans.

Cover and let it rise for 2-1/2 hours in a warm place.

Bake in a preheated oven at 375°F for 10 minutes, then reduce to 350°F for 50 minutes, until nicely browned.

Cool in the pan for 30 minutes, then remove from the pan and finish cooling on a wire rack.