Heat the oven to 350°F (175°C). Line an 8-inch square metal baking pan with parchment paper, leaving enough overhang on two sides to lift out the cooled brownies.

Halve the ripe avocado, remove the pit, and scoop about 5–6 ounces of flesh into a food processor or blender. Add the eggs, almond butter, low-carb sweetener, and vanilla, then process until completely smooth, scraping down the sides as needed.

Add the cocoa powder, coconut flour, baking soda, and salt. Pulse or blend only until the batter is uniform; do not overmix.

Fold in the sugar-free chocolate chips if using. Spread the thick batter evenly into the prepared pan.

Bake for 20–25 minutes, until the center is just set and a toothpick inserted in the middle comes out with moist crumbs rather than wet batter.

Cool the brownies in the pan for at least 20–30 minutes before lifting them out and slicing into 16 small pieces. They become firmer and fudgier as they cool.