01 - Preheat the oven to 350°F. Line an 8x8-inch baking pan with parchment paper.
02 - In a medium bowl, whisk together flour, cocoa powder, baking powder, and salt until evenly combined.
03 - In a separate large bowl, mix nut-milk pulp, sugar, melted coconut oil or butter, eggs, and vanilla extract until smooth and fully incorporated.
04 - Gradually fold the dry ingredients into the wet mixture using a spatula, stopping when just combined to avoid overmixing.
05 - Stir in chocolate chips and chopped nuts if desired for added texture and richness.
06 - Pour the batter into the prepared pan and smooth the surface evenly.
07 - Bake for 28 to 32 minutes, or until a toothpick inserted into the center emerges with a few moist crumbs.
08 - Allow to cool completely in the pan before cutting into squares and serving.