Preheat your oven to 175°C (350°F). Line an 8×8-inch baking pan with parchment paper, leaving a slight overhang on the sides to make removing the brownies easier later. Lightly grease if not using parchment.

In a large mixing bowl, mash the ripe bananas using a fork until mostly smooth. A few small lumps are fine and will add moisture and texture to the brownies.

Add your brown sugar, oil, vegan milk, and vanilla extract to the mashed bananas. Whisk or stir well until the mixture looks glossy and evenly combined. This step helps dissolve the sugar and ensures even sweetness throughout the brownies.

In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt. Sifting helps prevent cocoa clumps and results in a smoother batter.

Gradually add the dry ingredients to the wet mixture. Gently fold using a spatula until just combined. Be careful not to overmix, as this can make the brownies dense rather than fudgy.

Fold in the vegan chocolate chips and nuts (if using), distributing them evenly throughout the batter for consistent bites.

Pour the batter into the prepared pan and smooth the top. Bake for 28 to 32 minutes, or until a toothpick inserted into the center comes out mostly clean with a few moist crumbs.

Remove from the oven and allow the brownies to cool in the pan for at least 15 minutes. This helps them firm up and develop their fudgy texture. Lift out, slice into squares, and enjoy.