Preheat oven to 350 degrees F. Line a 12 cup muffin tin with baking liners and spray the inside of each liner with nonstick cooking spray.
Place black beans and 1 egg in food processor and process until beans are well blended.
Add two other eggs, maple syrup, coconut oil, vanilla and coffee; process again until smooth.
Next add in cocoa powder, baking powder and salt; process once more until smooth. Next fold in 1/3 cup of chocolate chips.
Divide batter evenly among muffin cups. Sprinkle remaining chocolate chips evenly among the tops of each muffin batter.
Bake for 25 minutes or until toothpick inserted into the middle of a muffins comes out clean. Place on wire rack to cool for 10 minutes, then remove muffins from tin and transfer to wire rack to cool completely.
Keep muffins for a day at room temperature, then transfer to fridge and place in an airtight container.