The most difficult part of this recipe to master is the caramel. You want to get it to a beautiful golden brown colour to get that bitter caramel flavour that contrasts so well with the tart apples.
Too pale and you don't get the fullness of flavour, but leave it too long and you will suddenly find your caramel too dark and then it just tastes burned! Don't be afraid to throw it away and start over.
...all it needs now is a dollop of ice cream.