Upside-down mandarin polenta yoghurt cake

Preheat oven to 180°C. Grease a 20cm (8-inch) square cake pan; line with baking paper.

Peel mandarins then scrape away white pith from the outside of the fruit; separate into segments. Arrange segments in alternating rows over base of pan.

Stir sugar and the water in a medium saucepan over low heat, without boiling, until sugar dissolves. Bring to the boil; boil without stirring, for 10 minutes or until mixture turns a golden caramel. Quickly pour half the caramel over mandarin segments. Cool remaining caramel in saucepan (don't worry that the caramel hardens on cooling, you reheat it later).

Beat butter, eggs, rind, polenta and extra sugar in a large bowl with an electric mixer until pale and fluffy. Stir in yoghurt and combined sifted ground almonds and baking powder. Spoon mixture over mandarins and caramel in pan.

Bake cake for 1 hour or until golden and a skewer inserted into the centre comes out clean. Stand cake in pan for 5 minutes before turning out onto a cake plate; cool until just warm.

Meanwhile, to make mandarin yoghurt stir sugar and juice in a small saucepan over low heat, without boiling, until sugar dissolves. Bring to the boil; boil without stirring for 3 minutes or until syrup reduces slightly. Cool. Combine yoghurt, rind and cooled syrup in a small bowl. Cover; refrigerate until needed.

Just before serving, heat remaining caramel over low heat, without stirring, until melted. Taking care, pour hot caramel over top of cake. Serve with mandarin yoghurt.