Preheat your oven to 350°F. Lightly spray a 9x13-inch baking pan with nonstick cooking spray, or you can line it with parchment paper.

In a medium bowl, whisk together 1¾ cups all-purpose flour, ¾ cup cocoa powder, 1 ½ teaspoons baking soda, 1 teaspoon baking powder, and ½ teaspoon kosher salt until well combined. Set aside.

In a large bowl, combine 1 cup buttermilk, ½ cup vegetable oil, 2 large eggs, 2 teaspoons pure vanilla extract, 1 cup granulated sugar, and ¾ cup light brown sugar using a Hand or stand mixer on medium-low speed and mix for 30 to 45 seconds, just until everything is smooth and well blended. Scrape down the sides of the bowl as needed.

Add the prepared dry ingredients to the wet ingredients in two additions, mixing on low speed for about 20 - 30 seconds each time, just until the flour is mostly incorporated. Avoid overmixing the batter. Stop the mixer when only a few streaks of flour remain.

Slowly pour the hot coffee (about 190 to 200°F, just off the boil) into the bowl containing the batter. Use a rubber spatula to gently stir the coffee into the batter by hand until smooth and well combined. The batter will be thin and glossy.

Pour the batter into the prepared pan and smooth the top. Bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs clinging to it. Let the cake cool completely in the pan before frosting.

While the cake is cooling, go ahead and heat-treat your all-purpose flour for the frosting. Place ¾ cup of all-purpose flour into a microwave-safe bowl and microwave it in short bursts, about 15 seconds at a time, stirring between each round. You’re looking for the flour to reach at least 165°F, which usually takes about 60 to 90 seconds total, depending on your microwave. Once it gets to the correct temperature, set it aside and let it cool completely before adding it to the frosting.

In a large mixing bowl, beat 1 ½ cups softened unsalted butter, ⅔ cup packed light brown sugar, ⅓ cup dark brown sugar, ¼ cup sweetened condensed milk, 1 tablespoon pure vanilla extract, and ½ teaspoon kosher salt for 2 - 3 minutes until creamy and fluffy.

Gradually mix in ¾ cup of heat-treated all-purpose flour and 3 ½ cups of powdered sugar, beating until smooth.

Add ¼ cup heavy cream and mix until combined and the frosting is spreadable. Finally, gently fold in 1 cup mini chocolate chips.

Once the cake has cooled completely, gently spread the cookie dough frosting over the cooled cake with an offset spatula. Sprinkle the roughly chopped Oreos across the frosting.

Slice the cake into squares and ENJOY! To make cleaner slices when serving, chill the cake for about 30 minutes before serving.