Ingredients :

• The apples — Golden for sweet melting, Granny Smith for a slight acidity that prevents the whole from being cloying. The ideal is a mix of the two. Avoid Fuji or Gala — too firm, they stay crunchy even after 40 minutes in the oven and create an unpleasant contrast with the cream.
• The heavy cream — Full-fat, really. Light cream at 15% fat doesn’t set the same way in the oven and gives a grainy texture, a bit like a failed flan. Here, the fat does all the binding work.
• The vanilla sugar — A store-bought packet works fine, but half a vanilla bean scraped directly into the cream really changes the result — a rounder, deeper flavor. Artificial vanilla dissipates during baking and leaves almost nothing.
• The brown sugar for the caramel — It melts slightly faster than white sugar and gives a light honey-colored caramel with a subtle licorice taste. Sprinkle it evenly — thick areas burn while thin areas are still caramelizing, and you end up with bitter spots.