Apple Crumble Cheesecake

Make the biscuit base

• Line the base of a 20cm deep springform or loose-bottomed cake tin with baking parchment.
• Crush the Oaties into fine crumbs. Add the ground cinnamon and mix well so that it is evenly distributed throughout the biscuit crumbs.
• Pour in the melted butter and mix thoroughly until all of the crumbs are coated and the mixture resembles damp sand.
• Tip the biscuit mixture into the prepared tin. Spread it evenly across the bottom and press down firmly to create a compact, level base. Place the tin in the fridge to chill while you prepare the remaining elements of the cheesecake.

Cook the Granny Smith apples

• Peel and core the Granny Smith apples and cut them into small diced pieces. Keeping these pieces fairly small means you get pieces of apple throughout the cheesecake rather than occasional large chunks.
• Melt the butter in a small frying pan over a low-medium heat. Add the diced Granny Smith apple, cinnamon, sweetener and water.
• Cook gently, stirring regularly, until the apple has softened but still retains its shape. Do not cook it down into apple sauce. You want soft, distinct little pieces of cinnamon apple to fold through the cheesecake.
• Transfer the cooked apple to a plate or bowl and leave it to cool completely. It must be completely cool before it is added to the cheesecake mixture.

Make the Bramley apple topping

• Peel and core the Bramley and cut it into larger bite-sized pieces.
• Melt the butter in a small pan over a low-medium heat. Add the Bramley, cinnamon, sweetener and water.
• Cook gently until the apple has softened but there are still visible pieces of apple. Bramley breaks down much more readily than Granny Smith, so stir it carefully rather than allowing it to turn completely to purée. If the pan becomes dry before the apple has softened, add a small splash more water.
• Remove from the heat and leave to cool completely.

Make the cinnamon crumble

• Preheat the oven to 160°C fan and line a small baking tray with baking parchment.
• Add the coconut flour, desiccated coconut, coconut flakes, porridge oats, ground flaxseed, sweetener and cinnamon to a bowl and mix together.
• Add the vanilla extract and cold butter. Rub the butter into the dry ingredients with your fingertips until you have a crumble mixture. Don’t make it completely uniform. A mixture of fine crumbs and some larger crumble pieces gives the finished topping much more texture.
• Scatter the crumble mixture over the lined baking tray and bake for approximately 8–10 minutes, until lightly golden and toasted. Keep a close eye on it towards the end of cooking as the coconut can colour quickly.
• Remove from the oven and leave the crumble to cool completely. Once cool, gently break up any pieces that have baked together, keeping some larger crunchy pieces rather than crushing everything into fine crumbs.

Make the cheesecake filling

• Add the cream cheese, mascarpone, sweetener and vanilla extract to a large mixing bowl. Beat together until smooth and completely combined.
• Pour the double cream into a separate bowl and whip until it has just thickened and holds its shape. Do not continue beating once it has reached this stage as you don't want to overwhip the cream.
• Add the whipped cream to the cream cheese and mascarpone mixture in 3–4 batches, gently folding each batch through before adding the next. Continue until all of the whipped cream has been incorporated and the filling is smooth, light and evenly combined. Take your time and fold rather than beat the mixture to avoid knocking too much air out of the whipped cream.
• Make sure the cooked Granny Smith apple is completely cold, then add it to the cheesecake mixture. Gently fold the apple through until the pieces are distributed throughout the filling.

Assemble the cheesecake

• Remove the chilled biscuit base from the fridge.
• Spoon the apple cheesecake filling over the biscuit base. Spread it right to the edges of the tin and smooth the top, taking care not to press all of the air out of the filling.
• Cover the cheesecake and place it in the fridge to chill overnight. This is a deep cheesecake with a generous amount of creamy filling, so it needs this longer chilling time to become properly firm before it is removed from the tin and sliced.

Decorate

• Once the cheesecake has chilled overnight and is completely firm and cold, carefully remove it from the tin and transfer it to a serving plate.
• Spoon the completely cooled Bramley apple pieces over the top of the cheesecake.
• Scatter the cooled cinnamon crumble generously over the apples and across the top of the cheesecake.
• Keep refrigerated until ready to serve. Cut into 16 slices using a sharp knife, wiping the blade between cuts for neater slices.