1. Heat oven to 180 DegC (160 DegC fan bake). Grease a 20cm springform cake tin and line the base with baking paper. Place butter and sugar in a bowl and beat until pale and creamy.
2. Beat in vanilla. Beat in eggs, one at a time. Stir in flour to just combine. Spoon cake batter into prepared tin. Arrange nectarine slices over the surface of the mixture, poking them slightly into the batter.
3. Sprinkle raw sugar and cinnamon over the fruit. Bake for one hour and 15 minutes, or until a skewer inserted comes out clean. Cover with foil towards the end of cooking to prevent over browning.
4. Cool in the tin for 30 minutes before removing to a wire rack to cool completely. Dust with icing sugar to serve.