Preheat your oven to 350°F (175°C). Lightly grease an 8×8-inch baking pan or line it with parchment paper to prevent sticking and make cleanup easier.

Place the rinsed and drained black beans into a food processor or blender. Blend until completely smooth. The texture should resemble a thick, creamy paste with no visible bean pieces.

Add the eggs, cocoa powder, sugar, melted butter (or oil), vanilla extract, baking powder, and salt to the blended beans. Blend again until the mixture becomes smooth and well combined.

Pour the batter into a bowl and gently fold in the chocolate chips if using. This step ensures they are evenly distributed throughout the brownies.

Pour the brownie batter into the prepared baking pan. Use a spatula to spread it evenly so the brownies bake uniformly.

Bake for about 20–25 minutes, or until the center is set and a toothpick inserted comes out with just a few moist crumbs.

Allow the brownies to cool in the pan for at least 15–20 minutes. This helps them firm up and makes slicing easier.