Preheat oven to 350 degrees F. Line an 8x8 pan with parchment paper and set aside.
In a large bowl, combine all of the crust ingredients, stirring until evenly combined. Press the crust dough into the bottom of the pan firmly and evenly.
Bake the crust for 12-15 minutes, or until just slightly starting to turn golden brown. Remove from the oven and set aside.
In a medium sauce pan, heat the maple syrup over medium heat, bringing it to a light boil while stirring constantly. Allow the maple syrup to bubble for 5 minutes, then add the mixed berries, cinnamon, and vanilla extract. Stirring constantly, allow the berry mixture to bubble and cook until thickened, about 10-15 minutes. Remove from the heat and set aside, allowing the filling to cool slightly.
In another large bowl, prepare the crumble topping by combining the roughly chopped walnuts, nut flour blend, shredded coconut, maple syrup, vanilla extract, almond extract, and salt. Drop the coconut oil into the mixture in pea-sized chunks, quickly working everything together with your hands. Place the crumble topping in the refrigerator for at least 5 minutes to allow the coconut oil to solidify again.
Pour the cooled berry mixture over the crust, spreading it out evenly over the crust and all the way to the edges of the pan. Top the berry filling with the crumble topping, making sure it gets evenly dispersed.
Bake at 350 for 15-20 minutes, or until the crumble topping begins to turn a light golden brown. Remove the bars for the oven and allow them to cool for at least 30 minutes.
Slice into bars, and enjoy