Line a baking sheet with parchment paper.

In a microwave-safe bowl, heat half the chocolate chips in 30-second intervals, stirring in between, until fully melted.

Pour the melted chocolate onto the lined baking sheet and spread into a rectangle.

Place it in the freezer for 10 minutes to set.

Heat treat the flour in the microwave for 60 seconds, then set aside.

In a large bowl, beat the butter, granulated sugar, brown sugar, milk, and vanilla until smooth. Mix in the flour until combined.

Take the chilled chocolate layer out of the freezer and spread the cookie dough evenly over it, pressing gently.

Melt the remaining chocolate the same way as before, then pour it over the dough and spread evenly.

Freeze for another 10 minutes until set, then cut into pieces and serve.