Preheat the Oven: Preheat the oven to 350°F (175°C). Line two large baking sheets with parchment paper or silicone baking mats.
Chop the Cookies: Chop 3-4 Oreos and the mini chocolate chip cookies into small pieces. Set aside the remaining 10 whole Oreos for stuffing into the cookies.
Mix Wet Ingredients: In a large mixing bowl, cream together 1 cup of softened butter, ½ cup of granulated sugar, and ½ cup of light brown sugar until light and fluffy (about 1-2 minutes). Add the 1 large egg, 1 tablespoon of vanilla extract, and ¼ to ½ teaspoon of blue food coloring. Mix until fully incorporated.
Combine Dry Ingredients: In a separate bowl, whisk together 2 cups + 2 tablespoons of all-purpose flour, ¾ teaspoon of salt, and ¾ teaspoon of baking soda. Gradually add this to the wet mixture, mixing just until combined. Be careful not to over-mix.
Fold in Mix-ins: Gently fold in the chocolate chips, chopped Oreos, and chopped mini chocolate chip cookies.
Form Dough Balls: Scoop about 10 tablespoons of dough per cookie and roll them into large dough balls. Press a whole Oreo cookie into the center of each dough ball, then top with more dough to fully cover the Oreo.
Bake: Bake the cookies for 8-10 minutes or until the edges are set but the centers are soft. Don’t over-bake; cookies should remain soft and chewy.
Cool: Let the cookies cool on the baking sheet for about 10 minutes, then transfer them to a wire rack to finish cooling completely.
