Preheat your oven to 350°F (175°C). This ensures your cookies bake evenly.
Line two baking sheets with parchment paper. This will help prevent the cookies from sticking.
In a medium bowl, whisk together the all-purpose flour, baking soda, salt, and Dutch-processed cocoa. Set aside.
In a large mixing bowl, use a stand mixer or hand mixer to cream together the room temperature unsalted butter, granulated sugar, and light brown sugar until the mixture is light and fluffy.
Beat in the eggs one at a time, followed by the vanilla extract. Mix until well combined.
Gradually add the dry ingredient mixture to the wet mixture, mixing until just combined. Be careful not to overmix.
Using a spatula, gently fold in the chopped white chocolate, semi-sweet chocolate, and chopped Oreo cookies until evenly distributed throughout the dough.
Using a cookie scoop, drop heaping tablespoons of dough onto the prepared baking sheets, spacing them about 2 inches apart.
Bake in the preheated oven for 10-12 minutes, or until the edges are set but the centers are still soft. Remove from the oven and let them cool on the baking sheet for 5 minutes before transferring them to a cooling rack.
Once the cookies are completely cooled, grab a glass of milk and enjoy your delicious Triple Chocolate Oreo Chunk Cookies!