In a mixing bowl, whisk together the sugar, xanthan gum, milk powder and salt.
Gradually whisk in 1 cup of the whole milk and continue whisking for a minute until the mixture thickens slightly. Whisk in the remaining milk, then whisk in the condensed milk, cream and vanilla. If mixture is already cold you can go ahead and churn. Otherwise, chill until very cold.
Transfer to the prepared ice cream container and process as per manufacturer's directions. If using the Oreos, just stir them into the soft ice cream before packing.
Notes
Variation: For coffee ice cream, warm the milk in a saucepan and add 1 ½ cup of regular or decaf coffee beans. Let steep for 1 hour. Drain the beans. Make recipe as directed using the coffee flavored milk. For a cheesecake base, reduce the cream by ¼ cup and add ¼ cup soft cream cheese. For Malted Milk, add 2 heaping tablespoons Carnation malted milk powder.