Preheat your oven to 350 degrees F. Lightly coat an 8x8-inch baking dish with nonstick spray. Line with parchment paper so that it overhangs two of the sides like handles, then coat again with spray. Set aside.
For the brownies: In a medium mixing bowl, combine the almond butter, cocoa powder, coconut sugar, maple syrup, egg, and vanilla. Let stand 5 minutes to allow the coconut sugar to absorb some of the moisture. Sprinkle the baking soda and salt over the top. Stir to combine. With a wooden spoon or spatula, fold in the chocolate chips. The batter will be very thick.
Scrape the batter into the prepared pan, then with a spatula or your fingers, press the batter into an even layer. Bake for 17 minutes, until the top is lightly dry and barely begins to puff. Let the brownies cool completely. (You can speed this process along in the refrigerator.)
For the topping: In a small saucepan, melt the chocolate together with the almond butter and coconut oil, stirring until smooth. Remove from the heat, then stir in the almond milk and vanilla until very smooth and evenly combined. The mixture will look very separate at first but will come together as you continue to stir. Spread over the top of the cooled brownies. Top with additional chocolate chips as desired. Refrigerate until the frosting is set, about 10 additional minutes. Slice and serve.
Store the brownies in an airtight container at room temperature for up to 4 days. Enjoy leftovers at room temperature or, to make them extra fudgy, warm slightly in the microwave.
Freeze for up to 2 months. Let thaw overnight in the refrigerator.