Drain the soaked almonds, but reserve some of the liquid. You may need to add a little a bit later.
Place in a blender or food processor along with the drained dates, pecans, vanilla extract, coconut oil, salt and cacao powder. Blend until you have a thick paste. You will need to periodically scrape the bowl down as this mixture is VERY thick.
You may find that the mixture gets "stuck" in the blender, if so, add a little of your soaking water, just to get it going again.
Once the mixture is fully amalgamated, scrape out into your prepared brownie pan and smooth out. Chill for an hour or so.
Once thoroughly cool, using a sharp knife, cut into small squares. You can now ice them, or keep them chilled in the fridge for 5 days. You can also freeze them, in a ziplock bag for about a month.