Preheat oven to 180⁰C. Grease and baking paper-line two 28cm x 38cm baking trays.
For chocolate cake, melt butter and sugar in a saucepan over a medium heat, stirring occasionally until sugar has dissolved. Remove from heat and allow to cool.
Place chocolate and cream into a bowl and over a saucepan of simmering water, stir occasionally until chocolate has melted and cream is incorporated. Remove from heat.
Pour chocolate mixture into butter mixture and stir until combined and smooth. Add eggs and mix to combine
Pour mixture into a prepared baking tray and scatter cherries on top. Bake for 40-45 minutes. Cake should be set on the sides but still a bit wobbly in the centre. Remove, allow to cool and refrigerate to cool completely.
For shortcrust sable, place all ingredients in a food processor and process until mixture comes together and resembles breadcrumbs.
Transfer to a floured board and knead gently to bring together. Shape pastry into a rectangle and refrigerate for 10-15 minutes to rest.
Roll dough to 3mm thick and 25cm x 35cm, keeping the rectangle shape. Transfer to a prepared baking tray and bake for 20-25 minutes or until golden brown. Remove and set aside to cool.
For grand marnier crème fraiche, whisk crème fraiche and icing sugar in a bowl until soft peaks form. Add grand marnier and whisk until combined. Fold in orange rind and refrigerate until required.
For pomegranate and sour cherry molasses, place all ingredients in a small saucepan and bring to the boil over a medium-high heat. Reduce syrup to half, remove from heat and allow to cool until required
To assemble cake, invert chocolate cake on to a cacao dusted board and remove baking paper. Flip shortcrust sable and place on top, removing baking paper. Lay a second chopping board on top of sable and flip so that cake is on top. Cut cake into 4cm x 10cm slices.
To serve, place a slice of chocolate and sable cake onto a serving plate with a quenelle of crème fraiche to the side, a drizzle of pomegranate sauce, a sprinkle of orange zest and a dusting of cacao powder. Decorate with edible flowers if desired.