1. Preheat the oven to 350° Fahrenheit (176° Celsius).
2. Line the bottom of an 8 inch square pan with parchment paper, or grease the pan well. Set aside.
3. Stir almond flour, cocoa powders, sweetener, baking powder, salt, and optional chocolate chips in a large mixing bowl until well mixed.
4. If not already liquid, melt the coconut oil or butter. Whisk the oil, eggs or flax eggs, coffee or water, and vanilla into the mixing bowl to form a brownie batter.
5. Spread the batter into the prepared baking pan. Smooth down the top with a spoon or spatula.
6. Bake on the center rack of the oven for 20 minutes, then remove and let cool on the counter. The almond flour brownies continue to firm up as they cool.
7. I like super fudgy brownies straight from the oven. If you prefer a firmer texture, you can refrigerate the cooled pan (loosely covered) overnight and they will firm up even more.
8. Frost if desired, and enjoy!
9. Leftovers should keep on the counter for a day, covered in the refrigerator for up to five days, or in the freezer in an airtight container for up to three months.