To the bowl of a food processor, add flour, sugar, baking powder, and salt. Pulse a few times to combine. (I like to use the dough blade for this.)
Add cold cubes of butter to the food processor and pulse until the butter is broken down into pea-sized pieces.
Add the vanilla and eggs to the food processor and mix until the dough comes together.
Turn the dough out onto a lightly floured surface and divide into two equal pieces. Cover each section tightly in plastic wrap, then gently press down to form a disc. Refrigerate for a minimum of 1 hour, or up to overnight.
Make the Filling
Place the standard metal blade into the food processor. Add dried figs, walnuts, and dates to the food processor and chop until small, even pieces form.
Add orange zest, marmalade, and Marsala wine. Pulse until the filling forms a chunky “paste”. Set aside.
Assembly
Preheat the oven to 400°F.
When the dough is chilled (it should be firm all the way through the disc), remove dough from the refrigerator, and unwrap. Using a bench scraper or sharp knife, cut each disc in half, to create 4 equal sized pieces. Rewrap 3 sections of dough and return them to the fridge.
Place the unwrapped dough on a lightly floured piece of parchment paper. Cover the top of dough with plastic. Using a rolling pin, roll over the dough to create a rectangle shape, approximately 6 inches by 14 inches. Remove the plastic wrap.
Divide the fig filling mixture into 4 sections. Form one section of the filling into a log shape, long enough to cover the length of the dough rectangle. Place the filling log in the center of the dough rectangle.
Fold the dough over the filling from one side and then the other. Flip the cookie log so the seam side is down; press gently to seal the seam closed.
The dough should still be firm; if it is soft, refrigerate for 15 minutes or so, until firm.
Using a bench scraper or sharp knife, cut the log, on the diagonal, into 1-inch sections. Arrange cookies 1-inch apart on a baking sheet lined with parchment paper.
Bake at 400°F for 10 minutes, or until bottom edges are golden brown. Remove from the oven and allow cookies to cool completely before decorating.
Decorate
To a medium bowl, add powdered sugar and 2 tablespoons cream; whisk to combine. Add more cream, 1 tablespoon at a time, until you have a thick, smooth glaze.
Dip the top of one cookie into the glaze, letting the excess drip off. Sprinkle nonpareils over the wet glaze, and transfer dipped cookie to a cooling rack to allow glaze to set (15-30 minutes). Repeat decorating with remaining cookies.
Notes
Storage: Store cookies in an airtight container on the countertop for 4-5 days or freeze for up to 3 months.Chill the dough well. It keeps the butter cold for a delicious, flakey shortbread type cookie. It also makes it much easier to work with the dough, and the cookies stay intact when filling, sealing, slicing, and transferring to the baking sheet.Sometimes raisins are used instead of dates. The filling can be made with a variety of nuts, like hazelnuts, pecans, almonds and/or walnuts.