Preheat the oven to 350F
Lightly grease standard-sized muffin pans (although greasing is not needed if using flexible silicon pans, which is recommended)
Drain the cooked black beans. Prepare the flax or chia eggs by combining the flax or chia meal with water. Stir and let stand for a few minutes to congeal.
Add the black beans to a food processor and puree for a few minutes. Add the flax or chia eggs, oil, cocoa powder, oat flour, maple syrup and vanilla extract. Blend thoroughly, gradually adding a few tablespoons of water at a time to achieve the right consistency - thick but spoon-able.
When the mixture has become very smooth, add the salt and baking powder and blend briefly to incorporate them.
Spoon the batter into the muffin pan and smooth the tops.
Bake for about 25 to 30 minutes, until the tops are dry and the edges begin to pull away from the pan.
Let the brownies cool completely before removing them from the pan.
Prepare the chocolate ganache frosting by melting the chocolate chips in the microwave and then whisking in the coconut milk.
Spread the frosting on the brownies and enjoy.

1 3/4 cup black beans, cooked until buttery soft, without salt
2 flax or chia seed eggs (made by combining 2 tablespoon of finely ground flax or chia seeds with 6 tablespoon water)
3 tablespoon walnut oil
3/4 cup cocoa powder
1/4 cup oat flour
1/3 cup grade A maple syrup, amber color
1 teaspoon vanilla extract
1/4 teaspoon salt
1 1/2 teaspoon baking powder
1/2 cup water, as needed to achieve the right consistency
3/4 cup semisweet chocolate chips, dairy free
1/4 cup coconut milk