Red velvet vacherin

Method

1. To make the cheesecake ice cream, process all the ingredients in a food processor until smooth. Churn in an ice-cream maker according to the manufacturer’s instructions, then transfer to an airtight container and freeze for 4 hours or until frozen.
2. To make the raspberry sorbet, place the sugar, glucose and water in a small saucepan over medium–high heat. Bring to the boil, stirring until the sugar dissolves, then leave to cool completely. Process the raspberries, lemon juice and syrup in a food processor to a smooth purée, then pass through a fine sieve, discarding the seeds. Churn in an ice‑cream maker according to the manufacturer’s instructions, then transfer to an airtight container and freeze for 3 hours or until frozen.
3. Preheat the oven to 120°C.
4. Using an electric mixer, whisk the egg whites and salt until soft peaks form. Whisking constantly, gradually add the caster sugar and whisk to stiff peaks. Sift over the icing sugar and cornflour, then fold to combine. Divide the mixture in half. Sift the cocoa over one portion and fold to combine, then fold in the food colouring.
5. Using a pencil, draw two 20 cm × 10 cm rectangles each on two sheets of baking paper (four rectangles in total), then place, pencil side down, on two baking trays. Using the templates as a guide, spread the white meringue over two rectangles, smoothing the tops. Spread the red meringue over the other two rectangles. Bake, swapping the trays halfway through, for 1 hour or until crisp but not coloured. Cool completely on the trays. The meringue will keep in an airtight container for 1 week.
6. To assemble, remove the ice cream and sorbet from the freezer to soften slightly. Meanwhile, line a 20 cm × 10 cm loaf tin with plastic wrap, allowing plenty of overhang, and place a layer of white meringue in the base (carefully trim the edges if necessary). Spread over half the ice cream and smooth the surface, then top with a layer of red meringue. Spread over the sorbet and top with the remaining piece of red meringue. Spread over the remaining ice cream, then finish, uneven edge up, with the remaining layer of white meringue (the vacherin will come up over the rim). Fold over the plastic wrap and freeze overnight so the meringue softens slightly.
7. To serve, carefully unmould the vacherin. Using a warm sharp knife, cut into 3 cm thick slices and serve immediately with fresh raspberries, if desired.