Set butter out to come to room temperature.

Adjust oven racks to the 2 middle positions and preheat oven to 350 degrees F (175 degrees C).  Line 2 large baking sheets with parchment paper. Set aside.

Put Cookies ‘N’ Cream pieces in a plastic bag, seal well, and smack with rolling pin until the pieces are pea-size.  Set aside.

In a medium bowl, whisk together flour (spoon into measuring cup, don’t scoop), baking soda, cream of tartar and salt. Set aside.

In a different bowl, cream together the butter, white sugar, and brown sugar until smooth, a couple minutes. Add 2 teaspoons vanilla and 1 teaspoon water then beat in the eggs one at a time.  Gently stir in flour mixture, and Cookies ‘N’ Cream Crunchers pieces.

Bake for 10 - 13 minutes, or until edges are nicely browned.  Transfer to wire racks to cool completely.

Cookies can be stored in an airtight container at room temperature for up to 5 days, and frozen for up to 1 month.   Freeze your baked cookies on baking sheets lined with wax or parchment paper first until firmly frozen, then transfer them to a freezer bag or another airtight container.  Otherwise, you'll end up with a mess.  

When thawing frozen baked cookies, take them out of the containers and let sit at room temperature so that condensation doesn't form and make them soggy.