1.Preheat oven to 160°C. Grease a deep 22cm round cake pan; line base and side with baking paper.
2.Drain cherries, reserving syrup. Coarsely chop or halve cherries; reserve for chocolate mousse. Stir the water into the syrup until combined; reserve.
3.Place butter and chocolate in a large heatproof bowl over a medium saucepan of simmering water; stir until just melted. Remove bowl from pan; whisk in sugar, extract and milk until just combined. Whisk in sifted flours and cocoa until just combined.
4.Pour mixture into pan; bake 50 minutes or until a skewer inserted into the centre comes out clean. Stand cake in pan 10 minutes before turning, top-side up, onto a wire rack to cool completely. Level top of cake if needed. Cut cake into three even layers.
5.Make chocolate mousse: Beat cream in a small bowl with an electric mixer until soft peaks form. Place chocolate in a large heatproof bowl over a medium saucepan of simmering water; stir until just melted. Remove bowl from pan; fold in cream, then 150g turkish delight, the walnuts and reserved chopped cherries.
6.Place base of cake on a platter or cake stand; drizzle with 2 tablespoons reserved syrup mixture. Top with half the mousse. Repeat layering with remaining cake, syrup and mousse, finishing with cake layer. Cover; refrigerate 3 hours or overnight until set.
7.Make chocolate glaze: Stir ingredients in a small saucepan over low heat until smooth. Set aside for 30 minutes or until thickened slightly.
8.Before serving, drizzle chocolate glaze over cake. Top with remaining turkish delight, chocolate pearls and pomegranate seeds.
Cake can be made a day ahead.Note