Cookies are the brown and white objects that looks like cookies and are ONLY found on the Wreck The Halls world. The cookies can either be on their own or contained within a block of ice or snow. Don't be alarmed as smashing them yields no score bonus. You likely will not destroy more than 300 before finishing the world. A good level to grind these on is Level 1-8. There are five cookies encased in snow which can easily be smashed with three birds you get relatively quickly. Pause and restart the level as soon as all the cookies are smashed or you run out of birds.