Preheat the oven to 170°C (150°C fan- forced). Line the base of a 22cm round pan with a baking paper.
Core and slice apples and place into a bowl sprinkle over brown sugar and mix to coat the apples and set aside.
In the stand mixer bowl with a flat beater accessory, beat the butter and caster sugar until very pale and creamy, scraping down the sides of the bowl when necessary.
Add the eggs, one at a time, beating well after each addition then add vanilla. Add half the flour and beat on speed 1 until just combined add the milk and continue to beat until just combined and then add remaining flour.
Spoon the mixture into the prepared cake pan and arrange the apples over the top of the batter.
Bake in a preheated oven for 55-60 minutes or until golden and a skewer inserted into the centre comes out clean.
Remove the cake from the oven and stand in the tin for 5 minutes before removing from the tin and transferring to a wire rack.
