1. Preheat your oven to 350°F (175°C) and line an 8×8 inch baking pan with parchment paper, allowing some overhang for easy removal.
2. In a medium bowl, whisk together the flour, cocoa powder, baking powder, and salt. Set aside.
3. In a large bowl, combine the melted butter and sugar, whisking until well incorporated.
4. Add the egg and vanilla extract to the butter-sugar mixture and whisk until smooth.
5. Stir in the mashed bananas until fully combined.
6. Gradually add the dry ingredients to the wet ingredients, folding gently with a spatula until just combined. Be careful not to overmix.
7. If using, fold in the chocolate chips for an extra touch of indulgence.
8. Pour the batter into the prepared baking pan, smoothing the top with a spatula.
9. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
10. Allow the brownies to cool in the pan for 10 minutes, then lift them out using the parchment paper overhang and transfer to a wire rack to cool completely before slicing.

These steps reflect the simplicity and joy that cooking should bring. Remember, the key is to enjoy the process — something my abuela always emphasized with her gentle, guiding hands.