Place the dry ingredients in a bowl and mix together.
Pour over the melted butter and mix until all combined and set aside.
Preheat the oven to 180°C (350°F), grease and line a 20cm round cake tin and set aside.
Place the oil, milk, vanilla extract, sugar and eggs in a bowl and mix thoroughly.
Sift in the flour, baking powder, baking soda, cinnamon and nutmeg and fold through. Mix until just combined.
Peel and dice your apples.
Coat the diced apples in the extra flour and cinnamon.
Pour half of the cake batter into the cake pan and spread in an even layer.
Top with half of the coated apple slices.
Top that with half of the crumble and repeat the process again.
Place in the oven for 45-60 minutes depending on your oven. Check at 35 minutes with a skewer inserted in the middle and keep checking every 10 minutes.
The skewer should come out clear, save from a few of the crumble crumbs.