Preheat your oven to 350 degrees Fahrenheit and lightly grease a 9×13-inch baking dish.

In a large bowl, whisk together the flour, cocoa, baking powder, salt, coffee powder, and spices so that all the dry goods are well mixed. Add in the chopped walnuts and toss to coat with flour so that the pieces don’t sink to the bottom of your bars.

Separately, mix together the rice syrup, molasses, brown sugar, oil, apple butter, and vanilla. Pour these wet ingredients into the bowl of dry, and stir just enough to bring everything together. A few errant lumps are just fine; be sure not to over-mix. The resulting batter will be extremely thick and sticky, to the point of being difficult to mix—don’t panic! Just make sure you get out any pockets of dry ingredients before proceeding.

Transfer the batter into your prepared pan and use lightly moistened hands to press it down into one even layer until it reaches all of the corners and sides. Sprinkle the chopped crystalized ginger over the top, and press gently into the unbaked bars with your fingertips.

Bake for 28–35 minutes, or until no longer shiny on top, firm around the edges, and highly aromatic. Let cool completely before either slicing into squares or cutting into rounds with a cookie cutter.