In a measuring cup or bowl, whisk together the whole milk, vanilla pudding mix, cinnamon, ginger, cloves, and allspice until smooth.
Whisk in the molasses and brown sugar until fully dissolved, making sure the molasses doesn't sink to the bottom.
Stir in the vanilla extract and heavy cream until fully combined.
Pour the base into a Ninja Creami pint container, secure the lid, and freeze on a level surface for at least 24 hours.
Remove the lid, place the pint into the Ninja Creami outer bowl, lock the lid, and install it in the machine. Press the Ice Cream button and let the cycle finish.
If the ice cream looks crumbly, run the Re-spin cycle. If it's still crumbly, add 1 tablespoon of milk and Re-spin once more until creamy.
(Optional) Make a well in the center, add crushed gingersnaps or gingerbread man cookie chunks, and run the Mix-In cycle.
Scoop and serve immediately for the best soft-serve texture, with a side of warm air fryer gingerbread man cookies if you're feeling festive.