Preheat your oven to 350°F and line a 9x13 inch baking dish with parchment paper, leaving some overhang on the sides for easy removal later. While the oven heats, whisk together the flour, cocoa powder, salt, and espresso powder in a medium bowl. The espresso powder won't make these taste like coffee—it deepens and intensifies the chocolate flavor, which is essential for balancing the sweetness of red velvet. Set this dry mixture aside.

In a large mixing bowl, melt the butter over low heat or in the microwave (avoid overheating), then add the sugar and mix until combined. I prefer using quality butter like Kerrygold because it creates a richer, more luxurious texture in these brownies. The mixture should be well blended but won't be fluffy like traditional creaming—this is normal since we're starting with melted rather than softened butter.

Add the room-temperature eggs one at a time to the butter-sugar mixture, stirring well after each addition to ensure proper emulsion. Then stir in the vanilla extract and red food coloring, mixing until the batter is a deep, vibrant red color and completely smooth. Room-temperature eggs incorporate more smoothly and create a better texture than cold eggs, which can break the emulsion and make the brownies grainy.

Add the dry ingredient mixture from Step 1 to the wet mixture from Step 3, stirring until just combined—be careful not to overmix, as this can develop too much gluten and make the brownies tough. The batter should be thick and fudgy-looking with no visible flour streaks. Stop mixing as soon as the dry ingredients are incorporated.

Reserve about 1/2 cup of the coarsely chopped cookies for topping. Gently fold the remaining 2.5 cups of chopped cookies into the batter using a spatula, being careful to maintain the texture—you want distinct cookie chunks throughout, not a uniform mix. Pour the batter into the prepared pan and spread evenly, then distribute the reserved cookie pieces across the top, pressing them down slightly so they stay in place during baking. I like to use cookies with visible cream filling layers so they create appealing texture contrast when you bite into the finished brownies.

Bake for 45 minutes, until a toothpick inserted in the center comes out with just a few moist crumbs—don't overbake, as these brownies will continue to set as they cool. Remove from the oven and let cool completely in the pan for at least 2 hours before cutting (or place in the refrigerator for 30-45 minutes if you're in a hurry). The cooling time is crucial because it allows the brownies to firm up enough to cut cleanly while maintaining their fudgy interior.