Combine ice cream, milk, and 4 of the Oreo cookies in your blender. Blend until pourable and pour into a glass.
Use the bottom of a glass or your hand to crush the final Oreo into small pieces (but not crumbs) and add the pieces to the the top of your shake or over whipped cream if desired. Serve and enjoy!
Notes
* Use ½ cup milk for a thicker shake, ¾ for a thinner one.This will make approximately 1½ to 2 cups, enough for one restaurant-sized shake or two smaller ones.Approximate nutritional information is for two shakes.