.Pour all the ice-cream base ingredients in a blender, blend until everything is mixed properly.
Pour the cheese mixture into a shallow,flat,rectangular air-tight container. Press plastic wrap on the top(this is important) and cover the container. And Jeep the container in a coolest part of your freezer.(for about 45 minutes).
Mean while in a heavy bottom pan,add blueberries,sugar,water and the vanilla bean. bring in to a boil.Keep stirring the mixture regularly. Once the berries are cooked,press slightly the berries in the back of the spatula. Stir the corn starch mixture slowly.Add the lemon zest.Simmer until the sauce is thick enough and coats back of the spoon. Cover the sauce and let it cool.
After 45 minutes, remove the ice-cream container from freezer.you might notice that the mixture has started to set from the sides. Using a spatula start breaking the mixture and using a spatula or a hand blender blend the mixture vigorously to break any Ice-Crystal formed. Repeat the procedure at least 2-3 times(i.e. freezing for 45 minutes and churning process).
Finally spoon blueberry sauce in to the ice-cream churned mixture. Stir it,to give a swirl look. Reserve any extra sauce to top while serving. (At this point If you want you can shift the ice-cream to the Serving container and then swirl the sauce).
Freeze the container covered at-least 5-6 hours or overnight.
15-20 minutes before serving,take the ice-cream out of the freezer and keep in the refrigerator. This makes easy to scoop out the Ice-Cream.
The Ice-Cream is best to be consumed with in 2 to 3 days.