Line a 500g loaf tin with clingfilm.
175 g Amaretti biscuits, 3 tablespoons Almond liqueur
Crush the biscuits into small pieces. Put them in a bowl and pour over the liqueur.
275 g plain dark chocolate
Break up the chocolate and put it into a medium-sized bowl.
300 ml double cream
Heat the 150 ml of the cream in a small saucepan, then pour over the chocolate.
75 g unsalted butter, 50 g caster sugar
Cream together the butter and sugar until pale and fluffy. Stir in the chocolate and cream mixture, then add the remaining 150 ml cream.
Spoon about one third of the chocolate mixture into the tin.
Mix the biscuits with the remaining chocolate mixture and press this down into the tin.
Chill the chocolate cake overnight until set.
Invert on to a plate and peel off the film.
If liked decorate with a drizzle of melted chocolate piped across the top.
Slice and serve.