Combine blueberries and sugar and let it sit for 30 minutes to macerate. 2. In saucepan, combine the blueberries and jam and cook on medium heat until soft, around 5 minutes. 3. Mash the blueberries with a fork, lower heat to medium-low and cook until thick, for 20 minutes. 4. Remove from heat and stir in lemon juice. 5. Refrigerate preserves until cool. Preserves will last in the fridge for up to 6 months in an airtight container. 6. Once cool, combine the fruit preserves, milk, cream cheese, and lemon zest in a blender and mix. 7. Add the ice cubes and blend until thick. Enjoy!