Thinly sliced apples soften in the oven, releasing their natural fragrance and giving every slice a deliciously fruity character. The light cake batter surrounds the fruit without overpowering it, allowing the apples to remain the star of the dish. A little lemon juice brightens their flavour and helps prevent the slices from browning while you prepare the batter. Sunflower oil gives the cake a moist, tender texture, while the eggs help the mixture rise into a beautifully soft crumb. Sprinkling the prepared tin with sugar creates a delicate sweetness around the fruit, and a final dusting of cinnamon sugar adds an inviting aroma.