Preheat the oven to 190 degrees Celsius. Add the oats, flaxseed meal, cacao powder, salt and baking soda to the bowl of a food processor, and blend until they form a flour-like consistency.
Next, add almond milk, coconut oil, egg and honey (or your choice of sweetener) and blend until well combined.
Add in the black beans (drained and rinsed) & blend for 20 seconds or until the mixture has formed a thick batter.
Taste the batter and add more honey and cacao powder if needed. You want the consistency to be similar to a normal brownie mix.
Line large pan with baking paper, then pour the batter into the lined pan. Smooth the top with a spatula and, if desired, sprinkle the nuts over the brownie mix.
Bake in the oven for 20 minutes. I like my brownies gooey on the inside, but if you prefer yours to be more well-done, bake them a little longer or until a knife comes out of the centre dry.
Removing them from the oven when they are still a little underdone is what makes them so fudgey and moist. The longer they bake, the dryer they will be. Eat while warm or store them in refrigerator for up to a week or can freeze some for 3 months.