OPTIONAL: 1 cup raw walnuts or raw pecans, chopped
Preheat oven to 325 degrees. Lightly oil the sides of an 9×13-inch baking dish and line the bottom with unbleached parchment paper.
In a large mixing bowl, whisk together the cacao powder, cassava flour and salt. Set aside.
In a high-speed blender, add the eggs, maple syrup, dates, coconut oil, applesauce, flaxseed and vanilla. Process on high until smooth and creamy.
Add the wet ingredients to the dry and mix well to combine. If using, stir in the dark chocolate chips and/or chopped nuts. Pour the mixture into the prepared baking dish and bake for 32-35 minutes or until a fork comes out clean.
Remove from oven and allow to cool slightly. Brownies are best served warm.