Truly awesome. You would never guess it contained beans.
Line a 11X13 baking pan with parchment paper. Preheat the oven to 325. Then put all of the ingredients, except the chocolate chips, and a 1/4 C of the walnuts, in a high powered blender and blend. If your blender is not so high powered, try blending just the eggs, agave, and black beans, and then add the rest of the ingredients except the chocolate chips, and a 1/4 cup of walnuts. just give it a little longer to incorporate all of the ingredients. (You don’t want chunks of black beans in your brownies!). Pour the mixture in the lined pan, then sprinkle the chocolate, and walnuts on top. Bake at 325 until the middle has set, about 30-45 minutes. Let cool COMPLETELY before cutting. Unlike most brownies these taste best refrigerated, so keep them in the fridge and serve cold.