Add the cottage cheese, pumpkin purée, milk, maple syrup, pudding mix, pumpkin pie spice, vanilla, and salt to a blender. Blend on high for 30 to 45 seconds, until the base is a uniform orange with no white flecks and no visible pumpkin strands.
Taste the base. It should taste slightly too sweet and noticeably too spiced — freezing mutes both. Adjust now.
Pour into an empty Ninja Creami pint, stopping at the MAX FILL line. Let the foam settle for 2 to 3 minutes, wipe the rim, and seal the lid.
Freeze for a full 24 hours on a flat, level shelf.
Remove the lid, seat the pint in the outer bowl, lock it into the machine, and run Lite Ice Cream (or CreamiFit on the Swirl).
The first spin will look crumbly. Dig a small well in the center, add 1 tablespoon of milk, and run Re-spin. Repeat once more if it isn't smooth — most pumpkin pints need two passes.
For mix-ins, make a well in the center, add them, and run the Mix-In program.
Serve immediately for soft-serve texture. To store, level the surface, replace the lid, and re-spin with a splash of milk before serving the rest.