Preheat the oven to 180 degrees celsius. Grease and line the cake tin with parchment paper.
In a large bowl, cream the butter and sugar until pale and fluffy.
Add and beat one egg at a time.
Add milk into the mixture.
Sift the cinnamon, flour and baking powder into the wet ingredients. Mix thoroughly.
Pour the batter into the cake tin.
Peel and halve the apples, slice them thin like you would do a hasselback.
Place the halved and sliced apples into the batter.
Sprinkle the streusel mixture on the batter.
Sprinkle a wee bit of cinnamon powder on top for extra kicks!
Bake for about 45 minutes, check to see if completely baked with a wooden skewer.
Once baked, let it cool on a cooling rack
Serve with a dollop of cream and tea!