Preheat the oven to 350˚F, and lightly butter a 9-inch pie pan with butter.
Spread the cranberries and apple chunks in an even layer across the bottom of the pie pan. Sprinkle 1/2 cup of the sugar and the cocoa nibs over them.
Using a wooden spoon, vigorously beat together the melted butter, flour, eggs, extract, orange zest, and the remaining 1 cup of sugar in a large mixing bowl to form a batter. Scrape the batter over the cranberry mixture. Dust the top with the turbinado sugar.
Bake for 40 to 45 minutes or until the cake is set. Test by inserting a knife - it should come out clean but moist. This is a moist cake which is probably why it was called a tart.
Place the cake on a wire rack to cool for about 20 minutes before slicing. Serve warm with vanilla ice cream, ideally drizzled with a little caramel.
As a final touch, dust the top with a spray of confectioners sugar, if desired.