Sift all the dry ingredients, including the flour, coffee, cocoa, baking soda and salt, into a bowl and set aside.
In another bowl mix together the maple syrup, water, sugar, flaxmeal mixture, and vanilla extract. Whisk together until well mixed.
Add the flour-cocoa mixture to this in 3 batches, mixing well after each addition using a ladle or spatula.
Stir in the walnuts. The batter will be really thick.
Prepare an 8 X 8-inch baking pan by lining it with parchment paper or aluminum foil. Leave an overhang on each side of the pan so you can easily lift the brownies out after they are baked. Spray the parchment or foil with non-stick cooking spray.
Pour the batter in and, using a spatula or the back of a spoon, spread evenly in the pan. At this point, you can sprinkle some chocolate sprinkles over the top for a nice finish.
Bake in a preheated 350-degree oven for 30-35 minutes or until a toothpick inserted in the center comes out clean.
Cool thoroughly on a rack. Lift out the brownies using the foil overhang as handles, and cut into squares. If you didn't use chocolate sprinkles, you can dust on some powdered sugar for a pretty finish.