Preheat the oven to 356°F.

Grease and flour a 9-inch pan, and set aside.

Peel, core, and thinly slice the apples. Place the slices and the lemon juice in a medium bowl, toss to coat, and set aside.

CAKE: Put the eggs, sugar, grated lemon zest, and salt in a large bowl, and beat until thick and creamy.

Add the flour, baking powder, and milk, and mix on low speed until combined.

Using a rubber spatula or a wooden spoon, fold two-thirds of the apples into the batter.

Pour the batter into the prepared pan and arrange the remaining apple slices, flat-side down, over the top.

Sprinkle with 1 tablespoon of sugar (optional).

Bake for 35 mins

Cool completely, then dust the cake with powdered sugar just before serving.