Add the rolled oats, milk, Greek yogurt, diced apple, cinnamon, caramel sauce, maple syrup, vanilla extract, and salt to a large mixing bowl.
Stir everything together until the ingredients are evenly combined and the caramel sauce is fully distributed.
Divide the mixture evenly among four jars or containers.
Seal the jars and place them in the refrigerator to rest overnight.
In the morning, remove the jars from the fridge and top each serving with the sliced apple and an extra drizzle of caramel sauce before eating.