Heat oven to 350 degrees and line a 9-inch square or round baking pan with parchment.
In a small, heavy-bottomed saucepan, stir together cranberries, granulated sugar and 1 tablespoon water. Stir the cranberries over medium heat until the sugar is completely dissolved and cranberries form a sauce that is syrupy and bubbling thickly, about 10 minutes.
In a separate saucepan, stir together the butter, brown sugar, milk, maple syrup and molasses over medium heat. Bring it to just barely a simmer and then remove it from the heat.
In a large bowl, sift together the flour, ginger, cinnamon, baking powder, salt, baking soda and black pepper. Beat in the butter-maple syrup mixture and then beat in the eggs. Stir in the ginger.
Scrape the batter into the pan. Drop fat dollops of cranberry sauce onto the surface of the cake batter. Drag a long, slender knife through the batter in a swirly design. Transfer the cake to the oven and bake it until the top is firm and a toothpick inserted in the center comes out clean, about 50 minutes.
