Prepare the apples. Wash and dry the apples well. Peel them, cut them into quarters, remove the core, and slice them thinly.
Prevent browning. Squeeze the lemon juice over the sliced apples and toss with your hands to coat evenly. Remove any lemon seeds.
Melt the butter. Gently melt the butter over very low heat. Avoid boiling. If using a microwave, heat for 30 seconds, then in 15‑second intervals until melted.
Mix the wet ingredients. In a large bowl, whisk together the melted butter, eggs, and vanilla extract. Do not overmix.
Add the sugar. Stir in the granulated sugar until combined. Add 1 tablespoon of cinnamon if you like a stronger spice flavor.
At this point, add the dry ingredients: the flour, a pinch of salt, and the baking powder.
Fold the dry ingredients into the wet mixture until fully absorbed and the batter becomes smooth and creamy.
Add the raisins and mix to combine.
Line your spring form pan with parchment paper.
Pour in the batter and roughly level the top with a spatula.
Preheat the oven to
356 °F. Arrange the thin apple slices on top of the batter, forming concentric circles as you like.
Mix one teaspoon of cinnamon with two tablespoons of brown sugar.
Using your hand, sprinkle the cinnamon‑sugar mixture evenly over the apples.
Bake for about 45 minutes, or until a toothpick inserted into the center comes out completely clean. This means the cake is ready.
Do not bake for more than 50 minutes or the inside may become too dry.
Remove the cake from the oven and let it cool slightly.
Remove the sides of the springform pan and transfer the cake to a cooling rack to finish cooling. If you prefer to serve it warm, transfer it to a serving plate and dust with powdered sugar, if desired.