Preheat your oven to 350°F (180°C). Grease an 8x8-inch baking dish lightly with oil or vegan butter, and line it with parchment paper.

In a microwave-safe bowl, melt together the vegan butter and half of the chocolate chips for about 30-45 seconds, stirring until smooth. Stir in the cane sugar until well combined, and allow to cool slightly.

In another bowl, sift together the flour, cocoa powder, baking powder, and salt. Gradually fold this mixture into your wet chocolate mixture without overmixing.

Spread the brownie batter evenly in the bottom of the lined baking dish and set aside.

In a separate bowl, melt the remaining vegan butter, then mix in the cane sugar, brown sugar, and plant milk. Sift in the flour and baking soda, folding until just combined.

Fold the remaining chocolate chips into the cookie batter, ensuring even distribution.

Dollop spoonfuls of cookie dough over the brownie layer, creating a layer that will meld together during baking.

Cover the baking dish loosely with aluminum foil and bake for 20 minutes. Remove the foil and continue baking for another 15-20 minutes until the cookie top is golden.

Let the brookies cool in the pan for about 15-20 minutes before lifting them out using the parchment paper and cool completely on a wire rack before slicing.