1. Preheat oven to 350°F (177°C). Prepare an 8×8-inch baking pan with parchment paper, leaving a little overhang for easy removal. You can use butter or oil if you don’t have parchment.
2. Melt the butter: In a large bowl, melt the butter in the microwave on medium power or in 10-second increments (so it doesn’t explode). Alternatively, melt in a pan on the stovetop and add to a large bowl.
3. Add the sugar: Stir the sugar into the butter for 30-60 seconds until it starts to melt into the butter. Let it cool for a minute or two so it doesn’t scramble the eggs in the next step.
4. Mix wet ingredients: Add the cocoa powder, eggs, and vanilla and whisk until smooth and glossy, 2-3 minutes.
5. Add dry ingredients: Add the almond flour over the wet mixture, then sprinkle the baking powder and salt evenly over the almond flour (this helps distribute the baking powder). Gently stir everything together until just incorporated. Stir in chocolate chips, if using. (This 1-bowl method saves you from washing an extra bowl.)
6. Bake: Spread the batter evenly in the prepared pan. Bake for 30–35 minutes, or until a toothpick inserted in the center comes out with moist crumbs (not wet batter).
7. Cool and slice: Let the brownies cool in the pan for 15–20 minutes before lifting them out. Transfer to a wire rack, cool completely (in the refrigerator, if possible), then slice into squares.

If possible, cool completely: Let brownies cool completely before slicing—almond flour brownies fall apart if cut warm. For best texture, refrigerate a few hours or overnight (covered), then reheat if desired.