Preheat your oven to 350°F (175°C).

Gather all your ingredients and tools, including a mixing bowl, baking sheet, parchment paper, and a large cookie scoop.

Line your baking sheet with parchment paper or a Silpat.

In a medium mixing bowl, cream together the butter, brown sugar, and granulated sugar until light and fluffy.

Add the egg and vanilla extract to the mixture and mix until smooth.

Sprinkle flour, corn starch, baking soda, and salt over the wet mixture and stir until just combined.

Fold in the chocolate chips and Halloween sprinkles.

Scoop out about 1/4 cup of dough, flatten it in your hands, and place one Oreo in the center. Fold the dough around the Oreo and roll it into a ball.

Place the balls on your baking sheet, ensuring they are spaced apart.

Bake for 10 minutes, noting they may appear slightly underdone.

Immediately add extra chocolate chips on top while cookies are still warm.

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