Cut puff pastry sheet into 4 circles and prick with a fork. Preheat oven to 400F.
Cut apples thinly and toss in lemon juice
Brush edges of puff pastry circles with heavy cream. Arrange apple slices on puff pastry in circle. Brush with melted butter. Sprinkle 1 tsp sugar all over each circle and a a generous pinch of cardamom.
Pop in oven at 400F for 25-20 minutes. Will become golden brown and slightly puffed when ready. Drizzle saffron caramel sauce on top.