01 - Preheat oven to 350°F. Line an 8x8 inch baking pan with parchment paper, allowing overhang on sides for easy removal.
02 - In a medium bowl, whisk together flour, cocoa powder, brown sugar, baking powder, and salt until well combined.
03 - Add melted coconut oil or vegan butter, plant milk, and vanilla extract to dry ingredients. Mix until just combined. Fold in chocolate chips.
04 - Press brownie batter evenly into the prepared pan using the back of a spoon or spatula.
05 - In a separate bowl, beat softened vegan butter, brown sugar, and granulated sugar until fluffy and well combined, about 2 minutes.
06 - Add plant milk and vanilla to butter mixture, mixing well. Gradually stir in flour, baking soda, and salt until just combined. Fold in chocolate chips.
07 - Carefully spread cookie dough evenly over brownie batter. Use spatula or water-moistened hands to press gently without displacing brownie layer.
08 - Bake for 30-35 minutes until top is golden brown and toothpick inserted in center comes out with a few moist crumbs.
09 - Cool completely in pan, about 1 hour. Lift out using parchment paper edges and slice into 12 squares.