• Cut the cake into slices and arrange them on a plate or wide, shallow dish. Drizzle all over with the orange liqueur.
• Drizzle over the orange and clementine juice.
• Whip the cream until thick but softly so, and spoon unfancily over the top of the saturated, not to say gloriously sodden, cake.
• Arrange the blackberries on top of the whipped cream, and then scatter with the orange zest.