In a mixing bowl, whisk the room-temperature cream cheese, sugar, and vanilla bean paste together until smooth and the sugar begins to dissolve.
Pour in the heavy whipping cream and whole milk. Whisk until fully combined and silky.
Pour the base into a Ninja Creami pint container, staying below the max-fill line. Seal with the lid and freeze on a flat, level shelf for at least 24 hours, until frozen solid.
Remove the lid, lock the pint into the Creami outer bowl, and run the Ice Cream program.
If the texture looks crumbly, run the Re-spin program until smooth and creamy. Add a tablespoon of milk before re-spinning if it's still dry.
Scoop, add your favorite toppings, and serve immediately for the creamiest texture.