In a small saucepan, mash together the sugar and 1 cup of blueberries with 1 tablespoon water.
Cook the sugar/blueberry mixture over medium-low heat for 5-8 minutes and allow them to simmer and thicken. Cool slightly.
In a blender, combine the cooled mixture, the remaining fresh blueberries, buttermilk, cream cheese, vanilla, salt, and lemon zest. Blend until mixed completely.
Stir in the cream/half n’ half and allow to chill for one hour.
Freeze in a 2-quart ice cream maker (like this one) according to manufacturer’s recommendations.
Serve immediately, or place in freezer for a while to harden it up a bit, if you prefer harder ice cream.