For the dough:
340g (3 sticks) unsalted butter, cold
3 3/4 cups all purpose flour
50g fresh yeast or 2 packages dry yeast
1/3 cup warm water
1 teaspoon salt
1/3 cup sugar
1 large egg
1 cup whole milk, room temperature
For the filling:
6 pitted prunes
6 dried figs
6 dried sour apricots
10 dried sour cherries
1/8 cup candied lemon
3 tablespoons sugar
2 teaspoons ground cinnamon
1/2 teaspoon ground cloves
1/2 teaspoon ground ginger
1/2 teaspoon ground cardamom
1/2 teaspoon ground nutmeg
1 tablespoon unsweetened cocoa powder
1/2 cup hazelnuts
1/2 cup walnut pieces
1/2 cup sliced almonds
1/4 cup pine nuts
3 tablespoons grappa
Grated zest of 1 small orange
2 tablespoons unsalted butter, melted
1 egg, lightly beaten with 1 tablespoon of water
To make the dough:
Cut the butter into small pieces and place it in a bowl. Sprinkle over 1/4 cup of the flour, and using your fingers, works the butter and flour together to make a uniform mixture. The butter should remain malleable. Shape the butter into a 10cm (4 inch) square, wrap it in plastic and set it aside in a cool place, but not in the refrigerator. Note: If you live in a hot climate, then put the butter in the refrigerator, but let it sit for a few minutes to become malleable before placing it on the dough.
In a small bowl, whisk together the yeast and warm water to dissolve the yeast. Add a pinch of sugar and let the mixture sit until foamy, about 5 minutes. In the bowl of an electric mixer, combine 2 cups of flour with the salt. Add the yeast mixture, sugar, egg and milk. Using the paddle, beat the ingredients until smooth. Switch to the dough hook and knead in the remaining 1-1/2 cups of flour for about 3 to 5 minutes or until you have a smooth, elastic dough. Place the dough in a greased bowl, cover with plastic wrap or a damp towel, and let it relax for 30 to 45 minutes.
Turn the dough onto a well-floured board and roll it into a large rectangle, about 40 x 40 cm (16 x 16 inches). Sprinkle the surface with some flour.
Place the square of butter in the middle of the rectangle of dough.
Fold the left and right sides over the middle, then the top sides over that; the goal is to make a "package" of dough.
Sprinkle the work surface and the top of the dough, as well as your rolling pin. Roll the dough in from the middle toward the top and bottom, making a long rectangle, maintaining the width, but increasing the length.
Fold the bottom upwards to the center, making a flap, and then fold the top over that, making an envelope. Turn the dough clockwise, so that the top flap faces the right; the dough should resemble a book. Once again, flour the work surface, the dough and the rolling pin, and repeat the rolling and folding process. You will end up with another book fold. Wrap the dough tightly in plastic wrap and refrigerate it for at least 4 hours or overnight.
For the filling and assembly:
To make the filling, place all of the dried fruits and nuts, sugar, cocoa and spices into the food processor.
Process to chop until the fruit-nut mixture is finely chopped and the spices and cocoa are thoroughly combined. Add the grappa and orange zest, and pulse to incorporate them.
Remove the dough from the refrigerator. If it was stored overnight, you will have to allow it to come to room temperature for about an hour before attempting to roll it. On a lightly floured board, roll the dough into a large rectangle, about 38 x 55 cm (15 x 22 inches).
Spread the filling evenly across the center of the dough, leaving a 2.5 cm (1-inch) border at the near end and each side.
Roll the dough, jellyroll style, starting from the bottom, wide side; you will wind up with a long snake.
Grease a 25cm (10 inch) springform pan. Roll the snake into a tight coil, and lay it into the pan, seam side down. Brush the dough with melted butter. Cover the dough with a towel and allow it to rise until doubled, about 1 hour.
Preheat the oven to 180C (350F). Brush the surface of the dough with egg glaze. Bake the Gubana on the center rack of the oven for 45 to 50 minutes or until golden brown. Rotate the pan halfway through the cooking period to ensure it browns evenly. Allow the Gubana to cool for 20 minutes in the pan, then carefully remove the sides of the pan to cool it completely. To serve, slice the cake in wedges. Gubana will keep wrapped in plastic up to 2 days.