Makes 1 cake
1. Preheat oven to 175C and grease and line a 22cm spring-form cake tin
2. Prepare your apples: Peel, halve and core the apples and then heat a pan over medium heat. Add 2 Tbsp butter + 1 Tbsp caster sugar + 2 Tbsp hot water + 2 Tbsp lemon juice to the pan, melt gently and then arrange the apple halves cut sides down in a single layer in the pan. Cook the apples until golden, adding an extra dash of water if necessary, and stirring as little as possible but swirling the pan for even browning as you need to. This will take 5–10 minutes depending on how juicy the apples are. Turn the apples over and cook on the rounded sides until they can be easily pierced with a knife, about 4-5 minutes. Remove the pan from the heat, transfer apples to a plate, cut sides up, and set aside to cool
3. Prepare your cake batter: To your food processor add all of the ingredients for the cake mix and blend until smooth
5. Arrange the apple halves cut sides down in the cake tin, spacing them as evenly as possible. Pour the cake batter over the apples and smooth it gently into all of the spaces around apples until you have a relativey smooth surface.
6. Bake until golden brown, fragrant and springy to the touch, 30-40 minutes, then leave to cool for 5-10 minutes, run a spatula gently around the inside edges of the tin to loosen the cake. Set a cooling rack upside down over the cake tin, flip over carefully to release the cake, gently scraping off any apples that stay behind and pressing them back into the cake and then transfer to a cake stand or large plate.
7. Serve the cake sliced into wedges, still warm or at room temperature and with double cream or whipped cream and an extra sprinkling of lemon zest.