1.Preheat oven to 160°C (140°C fan-forced). Grease deep 22cm-round cake pan; line base and side with baking paper.
2.Beat butter, rind and caster sugar in medium bowl with electric mixer until light and fluffy. Beat in eggs, one at a time. Stir in sifted flour, almond meal and juice, in two batches. Pour mixture into pan.
3.Bake cake about 50 minutes. Stand cake in pan 5 minutes; turn, top-side up, onto wire rack to cool.
4.Meanwhile, make mascarpone cream. Combine mascarpone, sifted icing sugar, rind and liqueur in medium bowl. Beat cream until soft peaks from; fold into mascarpone mixture.
5.Reserve 12 blackberries. Split cake into 3 layers. Place one layer of cake on serving plate; spread with half of the combined jam and liqueur. Spread with half of the mascarpone cream, then top with half of the blackberries. Repeat layering process, finishing with layer of cake. Cover; refrigerate 1 hour.
6.Serve cake dusted with sifted icing sugar and reserved blackberries.
Mascarpone needs to be handled carefully. Over-whipping, stirring, beating or whisking can cause it to curdle and separate, rendering it useless.Note