In a large mixing bowl, combine the softened butter, brown sugar, and granulated sugar. Using an electric mixer, beat the mixture on medium speed for 1–2 minutes until it turns light and fluffy.

Once your butter and sugars are well combined, add in the egg, vanilla extract, and blue gel food coloring. Mix on low speed until everything is thoroughly incorporated.

In a separate bowl, sift together the all-purpose flour, baking powder, baking soda, and salt. Gradually add this dry mixture to your wet ingredients while gently folding with a spatula.

Gently fold in the chocolate chips and mini cookies into the blue dough until they're evenly distributed.

Take a scoop of the dough, flatten it, place an Oreo in the center, encase it with more dough, forming a ball.

Refrigerate the formed cookie dough balls for at least 30 minutes or pop them in the freezer for 15–20 minutes.

Preheat your oven to 180°C (350°F), line a baking sheet with parchment paper, and bake for 12–15 minutes.

Let the cookies cool on the tray for about 5 minutes before transferring them to a wire rack to cool completely.