Make the Spiced Cranberry Juice per the directions in this post. (It would be best to make the day before you need the juice.)
In a large pitcher, add cranberry juice, vodka, orange and lime juice.
Mix well.
Pour into doubled up Ziplock bags or another freezer-safe container.
Freeze overnight or at least 4 hours.
Let thaw for 10 minutes before serving (depends on how slushy you want it).
Place about ½ cup of frozen vodka slush into a glass.
Top with lemon-lime soda.
Garnish with a cinnamon stick.
Notes
The Spiced Cranberry Juice can be made up to 3 weeks ahead of time if kept in the fridge in an air-tight container.Since the vodka won't freeze all the way, it will get slushy pretty quickly once removed from the freezer and especially when you add the lemon-lime soda.You can use a spoon to help break it up, also.