Preheat your oven to 350 degrees and line a buttered 9x13inch baking dish with parchment paper (leaving enough overhang so that it''s easy to pull out later). Set aside.
In a large bowl, whisk together the flour, graham cracker crumbs, baking powder, salt, ginger, cinnamon, cloves and nutmeg. Set aside.
In the bowl of your stand mixer, with paddle attachment fixed, cream together the butter and brown sugar until fluffy. Add each egg, one at a time, until incorporated. Now add the vanilla extract and molasses and mix again until combined, about 30 seconds.
Very slowly, with the mixer running on low, add the dry ingredients into the wet until all has been added and a soft cookie dough forms. Pour the dough into the prepared baking dish and smooth it over with a rubber spatula. Bake the gingerbread crust for 5 minutes then remove from oven. Set aside.
Layer the butterscotch chips, white chocolate chips, dark chocolate chips, coconut, pecans and walnuts on top of the partially cooked crust. Pour the sweetened condensed milk evenly over the 6 layers. Top with more chips if you wish. Cover the baking dish and bake for 30 minutes, removing the cover half way through cooking.
Remove from oven and let cool at room temperature for at least an hour, then cover and place in the fridge for another hour or two or until the top is set (I let mine sit overnight in the fridge). Cut into bars and store covered at room temperature, or for best results, store in the refrigerator. Enjoy!