1.Preheat oven to 160ºC (140ºC fan-forced). Grease a 20cm springform tin and line base with baking paper. Place tin on oven tray.
2.Beat cheeses, rind and sugar in a medium bowl with electric mixer until smooth; beat in eggs, one at a time. Stir in semolina and sifted flour, then buttermilk.
3.Pour mixture into tin, sprinkle with blackberries and bake about 1 hour. Cool cheesecake in oven with door ajar.
4.Refrigerate cheesecake 3 hours or overnight.
5.Serve dusted with sifted icing sugar, if desired.