In a mixing bowl or large measuring cup, whisk together the whole milk, heavy cream, sweetened condensed milk, vanilla extract, and sea salt until the mixture is homogeneous.

Pour the mixture into a Ninja Creami pint container, ensuring it does not exceed the maximum fill line.

Place the lid on the pint and freeze on a level surface in a standard freezer for at least 24 hours.

Remove the pint from the freezer and take off the lid; if a small peak has formed on the top, scrape it flat with a spoon to protect the blade.

Secure the pint in the Ninja Creami outer bowl and lock the lid in place.

Place the assembly into the machine and select the Ice Cream program.

Once the cycle finishes, check the consistency; if it appears crumbly or powdery, add one tablespoon of milk and select the Re-spin program.

Use a spoon to create a vertical hole in the center of the ice cream reaching the bottom of the pint.

Add the crushed Oreo cookies into the center hole.

Place the pint back into the machine and select the Mix-In program.

Remove from the machine and serve immediately to maintain the soft-serve consistency.