Gubana is a traditional spiral-shaped dessert from Friuli Venezia Giulia. The soft yeasted dough is rolled around a rich filling of walnuts, almonds, raisins, pine nuts, cocoa, citrus zest, and grappa, then baked until deeply golden.
Keep the filling moist but not runny, or it may leak from the dough during baking. Roll the dough tightly enough to preserve the spiral, but do not compress it so firmly that the filling is forced out. Gubana is often even better the following day, once the nut and citrus flavors have settled.
Place the raisins in a small bowl and pour the grappa over them.
Let the raisins soak for at least 30 minutes.
Combine the lukewarm milk, yeast, and 1 teaspoon of the sugar in a small bowl.
Let the mixture stand for 5 to 10 minutes, until lightly foamy.
Combine the flour, remaining sugar, salt, and lemon zest in a large mixing bowl.
Add the yeast mixture, eggs, softened butter, and vanilla.
Mix until a soft dough forms.
Knead the dough for 10 to 12 minutes, until smooth and elastic.
Place the dough in a lightly buttered bowl, cover, and let it rise for approximately 2 hours, or until doubled in size.
Drain the raisins, reserving any unabsorbed grappa.
Combine the walnuts, almonds, pine nuts, raisins, sugar, breadcrumbs, cocoa, cinnamon, and orange zest in a bowl.
Stir in enough of the reserved grappa to create a moist filling that holds together without becoming wet.
Transfer the risen dough to a lightly floured work surface.
Roll it into a rectangle approximately 12 by 18 inches.
Spread the filling evenly over the dough, leaving a 1-inch border around the edges.
Starting from one long side, roll the dough tightly into a log.
Coil the log into a loose spiral, tucking the outer end underneath.
Place the spiral in a buttered 9-inch round cake pan.
Cover and let it rise for 45 to 60 minutes, until visibly expanded.
Preheat the oven to 350°F (175°C).
Brush the surface gently with the beaten egg.
Bake for 40 to 45 minutes, until deeply golden and fully baked through.
If the top browns too quickly, cover it loosely with aluminum foil during the final 15 minutes.
Let the Gubana cool completely before removing it from the pan.
Dust with powdered sugar before serving.
