Rippled cranberry, fennel seed & mascarpone ice cream

1. Put the fennel seeds in a cold frying pan on a medium heat. Toast for about 1½ minutes, shaking the pan, until fragrant and a shade darker. Roughly crush with a pestle and mortar. 

2. Tip the cranberries into a saucepan and heat over a medium-high heat, stirring, for a couple of minutes, until the berries begin to burst. Add the sugar and crushed fennel seeds and simmer, stirring, for 8-10 minutes, until the cranberries are jammy and thick. Set aside to cool, then chill in a sealed container until needed (for up to 4 days). 

3. Using a balloon whisk, beat the mascarpone and vanilla seeds together in a mixing bowl. Gradually beat in the condensed milk until smooth and thick. Transfer to a loaf tin or other freezeproof container. Ripple the cranberry mixture in with a spoon, being careful not to overmix. Freeze the ice cream for at least 6 hours, but preferably overnight, before serving in scoops.