Prepare the dough: In the bowl of a mixer, combine 2 cups flour, 2 tablespoons sugar, ½ teaspoon sea salt, ¼ teaspoon baking powder, zest of 1 lemon, and zest of 1 orange. Add ¼ cup unsalted butter, cut into small pieces, and mix until the mixture resembles coarse crumbs. Add 4 large eggs and 1 tablespoon Marsala wine, mixing until a dough forms. If the dough is too sticky, switch to a dough hook and continue mixing. Wrap the dough in plastic wrap and refrigerate for 30 minutes.
Shape the dough: Divide the dough into 4 equal portions. On a lightly floured surface, roll each portion into a ¼-inch thick rope. Cut each rope into ½-inch pieces, then roll each piece into small balls, about the size of a hazelnut.
Fry the dough balls: Heat enough canola oil in a large, heavy-bottomed saucepan to reach about one-third up the sides. Heat the oil to 375°F (190°C). Fry the dough balls in batches for 2-3 minutes, or until golden brown. Use a slotted spoon to transfer the fried dough balls to a paper towel-lined plate. Allow them to drain and cool.
Prepare the honey coating: In a large saucepan, combine 1 cup honey, 1 tablespoon lemon juice, and 1 tablespoon orange juice. Cook over medium heat, stirring occasionally, until the honey mixture is slightly thickened, about 2-3 minutes.
Coat the dough balls: Add the fried dough balls and 1 ½ cups toasted hazelnuts or pine nuts to the honey mixture. Stir gently to coat all the pieces evenly. Allow the mixture to cool in the pan for 2-3 minutes.
Assemble and decorate: Spray a round platter lightly with cooking spray. Arrange the honey-coated dough balls into a mound or wreath shape. Sprinkle with colored sugar sprinkles and chopped candied orange peel (if using). Allow to set for at least 1 hour before serving.
Serve: Once set, serve the Pignolata at room temperature. Store any leftovers in an airtight container for up to 1 week.