Line baking pan.
Preheat oven to 350° F.
Rinse and drain the black beans. Then add to food processor and blend.
Add pureed avocado to food processor and blend well.
Add the cocoa powder, sweetener, baking powder, egg (or vegan flax egg), almond flour, vanilla extract, hemp hearts (or almond flour), and the optional cinnamon. Pulse everything until well combined.
Stir in the optional walnuts.
Pour the batter into the prepared baking pan lined with parchment paper. Smooth out the top with a spatula before placing in the oven for 15–20 minutes or until set.
Let cool completely before slicing into squares and serving. These gluten-free chocolate brownies are perfect on their own or topped with chocolate-avocado frosting, fresh berries, nuts or ice cream. Refrigerate. The brownies will firm up some more in the refrigerator.