Preheat oven to 350º. Spray a 9-inch pie plate with non-stick cooking spray. Set aside.

Melt the butter in a large, microwave-safe bowl. Mix in the sugars, then the vanilla. Then stir in the egg.

Whisk together the flour, baking soda, and salt in a medium bowl. Then mix into the butter mixture just till combined. Add the chocolate chips and ½ cup of the candies. Reserve the remainder of the candy to garnish the cookie cake when it comes out of the oven. Mix well.

Scrape the dough into the prepared pan, then smooth the top with an offset spatula.

Bake for 25 minutes or till the top is golden brown. Remove from the oven and gently press the remaining candies across the surface of the cookie cake while it's hot.

Cool before slicing.