To a blender, add the cooked apples (with all that delicious spicy caramel), milk, heavy cream, brown sugar, condensed milk, spices, salt, and vanilla extract. Blend over high speed until smooth. Transfer the mixture to a medium saucepan and bring to a simmer over medium heat. Once the mixture has been brought to a simmer, turn off the stove, give it a stir and allow the mixture to steep for 30 minutes to 1 hour.
Once your mixture has steeped, prepare a large bowl with ice water - A bowl large enough to hold a smaller bowl for your egg custard. Separate your egg yolks into the bowl.
Add your steeped apple mixture into the egg yolks, whisking constantly until completely incorporated. Add the mixture a medium saucepan and cool over medium/low heat, stirring THE ENTIRE TIME until the mixture thickens and coats the back of a wooden spoon. Test by dipping the wooden spoon into the custard and running your finger down the spoon. If the mixture doesn't come together when you run your finger, it's ready. This can take anywhere from 5-8 minutes.
Pour the apple mixture in the bowl lined with the strainer, pressing and stirring the solids to extract as much liquid as possible. If apple bits escape the strainer – That’s a good thing. Allow the custard to cool completely, stirring every once in a while to help it along.
Freeze according to your ice cream maker's directions and once your ice cream is frozen, fold in the reserved cup of cooked apples. Pour into an airtight container and allow to freeze completely. Serve topped with nilla wafer crumble.