1.To make lemon compote, preheat the oven to 150°C (130°C fan-forced). Thinly slice the 2 whole lemons and cut the slices into quarters; remove the seeds. Layer the quarters in a medium ceramic ovenproof dish. Combine the sugar, rosemary and water in a small saucepan; stir over a low heat until sugar is dissolved. Bring to the boil. Simmer, uncovered, for 1 minute. Remove from the heat; pour the syrup over the lemon quarters. Cover lemon mixture with baking paper then seal the dish with foil. Bake for 30 minutes. Remove the foil and paper; bake for a further 30 minutes or until the syrup is thick and the lemons are caramelised. Cool.
2.Preheat oven to 180°C (160°C fan-forced). Grease a 20cm round cake pan; line base and side with baking paper.
3.Beat the butter and sugar in a small bowl with an electric mixer until pale and creamy. Beat in the eggs, one at a time, beating until combined between additions. Stir in the almond meal, polenta and baking powder; then stir in the rind, juice and orange blossom water.
4.Spread the mixture into prepared pan; smooth the surface. Bake tor about 1 hour or until cooked when tested with a skewer. Cool cake in the pan.
5.Serve cake with lemon compote and thick cream, if desired.
Cake suitable to freeze. Not suitable to microwave. Orange blossom water, also known as orange flower water, is a concentrated flavouring made from orange blossoms. It is available from Middle Eastern food stores, delicatessens and some supermarkets.