Preheat your oven to 350°F. Line an 8-inch square baking pan with parchment paper and set it aside.
In a blender or food processor, place the avocado flesh, coconut oil and sugar, and blend or process until smooth
In a large bowl, place the eggs, vanilla, and avocado mixture, and whisk to combine well.
Add the cocoa powder, baking soda, salt and flour, mixing to combine after each addition. The mixture will be thick, soft and shiny.
Scrape the batter into the prepared pan and, using a wet spatula, spread into an even layer.
Tap the bottom of the pan on the counter firmly to break any large air bubbles.
Place the pan in the center of the preheated oven and bake until set in the center and a toothpick inserted comes out with a few moist crumbs attached, about 20 minutes. Do not overbake.
Remove from the oven and allow to cool completely in the pan.
After 10 minutes at room temperature, the pan can be placed in the refrigerator to chill, which will make slicing a bit easier.
Remove from the pan by holding onto the parchment paper and placing on a flat surface.
With a sharp knife or pizza wheel, slice into 9 equal squares and serve chilled or at room temperature.
Notes
Nutritional information is an estimate per brownie, assuming you have sliced 9 equal sized brownies. It is created using an online nutritional calculator and should not be relied upon.