Step 1: Prepare the Baking Dish and Preheat the Oven - Start by preheating your oven to 350°F (180°C). To ensure easy removal later, grease and line an 8×8-inch baking dish with parchment paper or cooking spray.

Step 2: Make the Brownie Layer - In a large bowl, combine vegan butter and chocolate chips. Heat them in the microwave for about 30 seconds or until melted completely. Stir in the cane sugar until well mixed, and let it cool down for a few minutes. Meanwhile, mix flax meal and plant milk in a small bowl, allowing it to sit for 2-3 minutes to thicken. Once thickened, stir this mixture into the melted chocolate mixture. Sift the flour, cocoa powder, baking powder, and salt into the bowl, then fold everything together gently. Press the brownie batter evenly into the prepared baking dish.

Step 3: Prepare the Cookie Dough Layer - Melt more vegan butter in a separate large bowl in the microwave for 20-30 seconds. Whisk in the cane sugar and brown sugar until they are mostly dissolved. Stir in the plant milk and vanilla extract. Sift in the flour, cornstarch, baking soda, and salt, then gently mix until combined. Fold in chocolate chips. The dough will be quite thick, so you may need to cut or mash the chocolate chips into the dough for an even distribution.

Step 4: Assemble the Brookies - Using a cookie scoop, place dollops of the cookie dough on top of the brownie layer in the baking dish. Spread it evenly over the brownies to form a unified layer.

Step 5: Bake the Brookies - Loosely cover the baking dish with foil and bake in the preheated oven for 20 minutes. After 20 minutes, remove the foil and continue baking for another 15-20 minutes or until the top turns light golden brown.

Step 6: Cool, Slice, and Serve - Once baked, let the brookies cool in the pan for 15-20 minutes. This cooling period will further solidify the treats. Slice them into squares and serve. For an extra treat, optionally top each brookie with a sprinkle of flaky salt and a scoop of vegan vanilla ice cream. Enjoy!