Toast walnuts at 170°C for 8–10 minutes. Blend with dates, cocoa, salt, and cinnamon to form a paste. Press into a greased 6-inch ring and freeze for 10 minutes.
Boil apples until tender, drain, and cool. Blend with melted chocolate, coffee, and salt into a smooth mousse.
Pour mousse over the base and refrigerate for 2–3 hours.
Demould with a hot knife, top with whipped cream, dust with cinnamon, and garnish with walnuts.
