Christmas ice-cream cake with festive crumb

1.For ice-cream, bring milk and cream to a simmer in a large saucepan over medium heat. Meanwhile, whisk yolks and sugar in a large bowl until pale (4 minutes). While whisking continuously, gradually add milk mixture. Return to pan and cook, stirring continuously, over medium heat until mixture coats the back of a spoon. Remove from heat and whisk in xanthan gum, then Christmas cake and citrus peel until combined. Place bowl over an ice-water bath and stir to cool completely. Churn one-third of the mixture in an ice-cream machine until firm.

2.Meanwhile, grease a 22cm bundt tin (2-litre capacity). Spoon ice-cream into the tin, scatter over half of the green and red cherries and place in the freezer. Repeat churning with another third of the mixture, then spoon into tin and scatter over remaining cherries. Return tin to freezer. Meanwhile, churn the final third of the mixture; add to tin and freeze for 6 hours or overnight until firm.

3.For festive crumb, preheat oven to 150°C fan-forced. Grease and line a large oven tray with baking paper. Place all the ingredients in a large bowl and, using your hands, knead until incorporated. Scatter mixture over prepared tray and bake, frequently breaking it up and stirring with a metal spoon until golden and crisp (20 minutes). Transfer tray to a wire rack and leave to cool. Place three-quarters of the oat mixture in a food processor and pulse until coarsely chopped; return to remaining oat mixture and toss to combine.

4.For chocolate and whisky sauce, combine 500ml water, sugar, cocoa, vanilla and a pinch of salt in a saucepan over medium heat, whisking continuously, until thick enough to coat the back of a spoon (8 minutes); remove from heat and stir in whisky. Place pan in an ice bath and stir until cold. Transfer to an airtight container until required.

5.To remove ice-cream cake from tin, dip tin in hot water for 5 seconds. Invert onto a tray lined with baking paper (you will need to be quite firm to dislodge it). The outside should be slightly melted; this will help the crumb to stick. Scoop up handfuls of the crumb and pat around the ice-cream cake to cover evenly, then place in freezer to firm (1 hour).

6.To serve, transfer ice-cream cake to a cake stand and drizzle over chocolate and whisky sauce.