Peel 6-8 apples, cut each in half, remove the cores, and thinly slice about 1-2mm thick using a mandolin or knife
Place sliced apples in a large mixing bowl and add the zest and juice of one orange
Mix thoroughly with your hands until every slice is completely coated
In a separate bowl, whisk together eggs and caster sugar until pale and sugar is fully dissolved
Add melted butter, milk, vanilla, cinnamon and nutmeg to the egg mixture and whisk until smooth
Add plain flour and whisk until just combined
Pour the batter over the sliced apples and mix thoroughly so all slices are evenly coated
Line a loaf tin with parchment paper, leaving overhang on the sides
Transfer the coated apple slices into the tin, packing them tightly and compactly
Pour any remaining batter over the top of the apples
Preheat oven to 170°C (338°F) and bake for about 1 hour, covering loosely with foil if browning too quickly after 40-45 minutes
Let the cake cool in the tin for 15 minutes, then brush the top with warm apricot jam
Allow the cake to cool completely before lifting out and slicing
Dust lightly with icing sugar and serve warm or at room temperature
