First, place dry ice in a paper bag and smash it by rolling over the bag with a rolling pin, or by breaking it into small pieces with a hammer or mallet. Mix together the other ingredients in a mixing bowl, and then slowly mix in the dry ice pieces until desired consistency is reached.
Once you have mixed all the ingredients together, make sure your dry-ice ice cream is warm enough to eat. Eating your own homemade ice cream is no fun if you have frostbite on your tongue.
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