Preheat oven to 350o degrees and adjust the oven rack to the middle position. Line the cake pan with a piece of parchment paper wide enough to fit the pan and long enough to overhang the sides of the pan - this creates a sling to lift the cake out of the pan.
Make the Maple Syrup Caramel Sauce ahead of time. Double the recipe if you want extra caramel on top of your cake before baking, plus extra to drizzle on before serving.
Core and thinly slice the apple. Depending on how you arrange the apple on top of the cake, you may have extra slices. For this recipe, I only used about ¼ of the apple.
In a small mixing bowl, whisk together the flour, cornmeal, baking soda, baking powder, salt, and cinnamon.
In a medium mixing bowl, whisk together the apple cider, applesauce, maple syrup, and vanilla extract. Mix in the egg until incorporated, then mix in the melted butter.
Add ½ of the dry ingredients to the wet ingredients. Gently whisk until just incorporated. Add the remaining dry ingredients and whisk until no dry streaks remain.
Pour the cake batter into the prepared pan. Arrange the apple slices in concentric circles on top of the batter. Pour ¾ (if you doubled the recipe - all if you did not) of the Maple Syrup Caramel Sauce over the top of the apples. Optional - sprinkle chopped pieces of crystallized ginger over the top.
Bake for 18-22 minutes, or until a toothpick inserted in the middle comes out mostly clean. Cool in the cake pan on a wire rack for 10 minutes. Use the parchment sling to gently remove the cake from the pan, remove the parchment, and cool completely on a wire rack.
Drizzle with the remainder of the Maple Syrup Caramel Sauce before serving, and enjoy!