Preheat the oven to 350ºF and line an 8-inch square baking dish with parchment paper. (I like to lightly spray the pan with oil first, then add the parchment paper so that it will stick in place.)
In a large bowl, combine the coconut flour, eggs, cacao powder, sugar, salt, and vanilla. Stir well until no lumps remain. (This is sometimes easier to mix using a whisk to help break up clumps.)
Add in the melted coconut oil, and stir again until the batter is smooth. Fold in the chocolate chips, if using.
Pour the batter into the prepared pan and smooth the top with a spatula. Bake at 350ºF for 30 minutes, or until the center doesn't wiggle when you gently shake the pan.
Let the coconut flour brownies cool completely in the pan, then slice them into 16 pieces and serve. Because these brownies are rich and moist, I recommend storing them in an airtight container in the fridge for up to 5 days, for the best shelf life. Let them come to room temperature again before serving at a party, for the best flavor.
