Preheat the oven to 350 degrees F.
Grease a 9 inch springform pan and set aside.
In a large bowl, beat together the softened butter and sugar until creamy for about 1 minute.
Beat in the eggs one at a time until well combined.
Stir in the vanilla extract and the lemon zest.
In a separate medium sized bowl, whisk together the flour, baking powder and salt.
With the mixer on low, add the flour mixture to the butter mixture, alternating with the almond milk while making 3 additions of dry and two of wet.
Fold in the grated apple pieces
Spoon the batter into the prepared pan and level the top with an offset spatula or the back of a spoon.
Starting at the outer edges of the cake, place the apples slices upright while pressing down a little into the batter. Do this for 1 whole circle and on the next round place the slices in front of two joined slices. Continue overlapping the slices till you reach the center
If you want to add an apple rosette in the middle leave a little space and do this...line 6 slices of apples lengthwise while overlapping them slightly and start rolling from one end to the opposite end while shaping a rose then place in the center top of the cake.
Bake in a preheated oven for 40 minutes or until a cake inserted in the center comes out clean.
While still warm gently brush the top of the cake with the warm maple syrup and allow to cool. This will give the apples a pretty sheen.
Dust the cake with the powdered sugar just before serving