Pre-heat the oven at 180C.
Line a 9x9 inch baking dish with parchment paper.
Prepare the flaxegg by mixing the ground flax with water. Let it set for a few minutes.
Add all ingredients (including the flaxegg) into the food processor, except for the berries and walnuts. Blend until smooth, which will take only a few minutes. Make sure to scrape down the sides of the food processor.
Transfer the batter into a bowl, mix in the berries and chopped walnuts.
Pour the batter into the lined baking dish. Use a spatula to even out the surface.
Bake for around 40-45 minutes, until the top is dry and cracked. Once removed from the oven, let cool in the baking dish completely before removing, and slicing into squares. They should be fudgy, and not completely solid in the middle - that's always the best kind of brownie IMHO!
If you feel extra fancy, melt the dark chocolate with coconut oil and drizzle evenly on top.
Enjoy as it is, or serve alongside some gut-loving greek-style yoghurt (or your fave yoghurt) for the full experience.
