1. In a small pan heat the cream, sugar and butter just below boiling point. 

2. Add the broken-up chocolate and liqueur and give it a good stir until you get a smooth mix.

3. Fold in the biscuits and mix well.

4. Brush the loose based cake tin with vegetable oil and fill as evenly as possible.

5. Refrigerate for at least 6 hours.

6. Sprinkle with powdered almonds and serve with whipped cream.