Preheat the oven to 180 degrees C. Grease and line a 23cm x 34cm ovenproof dish.
Base: Mix all the ingredients together and press evenly into bottom of the prepared dish. Cook for 12 minutes until lightly browned then remove from oven and cool.
Apple Filling: Mix the apples and white sugar together then heat, stirring until sugar dissolves. Put aside.
Caramel: In a medium size saucepan over a medium heat, melt the condensed milk, brown sugar and butter, stirring until boiled. Lower the heat and stir for 5 minutes until thick. Remove from heat and stir in the salt. Cool slightly.
To Assemble: Drain any excess fluid from apples then spread the apples evenly over the base.
Spread the caramel evenly over the apples. refrigerate until cold, about 2 hours.