Preheat the oven to 350°F and prepare an 8×8-inch baking pan by greasing it lightly.
In a food processor or blender, combine the black beans, eggs, maple syrup, melted coconut oil, cocoa powder, salt, baking powder, and vanilla. Blend until completely smooth.
Remove the blade and fold in chocolate chips and walnuts if using. Alternatively, you can sprinkle the walnuts on top of the batter once it is poured into the pan.
Pour the batter into the prepared pan and spread evenly.
Bake for 35 minutes, or until the center is set and a toothpick inserted in the middle comes out clean.
Allow the brownies to cool completely before cutting into squares. Serve and enjoy your fudgy black bean brownies.