Prep oven and pan. Preheat oven to 350°F (180°C). Line an 8-inch square pan with parchment paper or grease lightly with cooking spray.
Mix the batter. In a large mixing bowl, whisk together the mashed avocado and oil to combine, taking care to break up any big chunks of avocado. Add in the flour, cocoa powder, sugar, baking soda, vanilla extract, salt, and water (or coffee) and stir until combined. Use a spatula to gently fold in 1 cup of the chocolate chips until just combined.
Bake. Pour the batter into the prepared pan and spread it in an even layer. Sprinkle evenly with the remaining 1/2 cup chocolate chips. Bake for 20 minutes, or until a toothpick inserted into the center comes out clean. (Be careful not to over-bake, or else the brownies will move from being more fudgy to much more cake-like in texture.)
Cool. Transfer the pan to a wire rack and let cool for at least 20 to 25 minutes before serving.
Serve. Cut into squares, serve and enjoy!
Notes
Avocado: Mash the avocado very well with a fork and then press the mash firmly into a measuring cup to ensure that you have the proper amount. Alternatively, if you don't have avocado on hand, you're welcome to sub in an additional 1/4 oil. Or if you would like to omit the oil entirely, you can instead use a full 1/2 cup of mashed avocado.Water or coffee: I prefer to use brewed coffee in place of water, which really helps to enhance the flavor of the chocolate. You are welcome to use caffeinated or decaf coffee. Or plain water will work just fine too.Source: Recipe slightly adapted from The Pastry Affair. I also edited the recipe in 2022 to slightly reduce the amount of water (or coffee) from 3/4 cup to 2/3 cup and add vanilla extract.