Peel the apples, cut them into cubes, and cook until soft.
Meanwhile, melt the dark chocolate by placing the chocolate chips in a heatproof glass bowl set over the saucepan with the apples (making sure the bowl does not touch the water).
Transfer the cooked apples to a blender and blend until smooth.
Pour the apple purée over the melted chocolate and blend again until fully combined and silky.
Pour the mixture into a removable-bottom circular baking pan, tap gently to release any air bubbles, and let it rest at room temperature for 30 minutes.
Then transfer to the fridge and chill for at least 6 hours before serving.