1. Heat blueberries, water, Truvia and xanthan gum to boil for 2 minutes. Refrigerate 15-20 min. 2. Process cream cheese, sour cream, and heavy whipping cream until fluffy. 3. Spoon into freezer-proof container. Top with spoons full of the blueberry mixture; swirl so you get swirls of blueberry with swirls of ice cream. 4. Freeze 4-5 hours until firm.