700 mlmilk300 gmsweetened chestnut purée (see note)3stalks of rosemary6egg yolksTo serve:candied chestnuts (optional, see note)Rosemary syrup165 gm(¾ cup) caster sugar1 tbsprosemary leaves
Combine milk, chestnut purée and rosemary stalks in a saucepan and stir over medium heat until purée dissolves (4-5 minutes). Bring to the simmer and cook for 5 minutes. Remove from heat and stand for 10 minutes to infuse. Meanwhile, whisk egg yolks until pale (3-5 minutes), pour over milk mixture, whisking continuously to combine. Return to pan and cook, stirring continuously, until mixture thickly coats the back of a spoon (4-5 minutes). Strain into a bowl placed over ice to cool, then freeze using an ice-cream machine according to manufacturer’s instructions. Makes about 1 litre.
Meanwhile, for rosemary syrup, combine sugar and 150ml water in a small saucepan and stir over medium-high heat until sugar dissolves. Add rosemary, bring to the boil and cook for 5 minutes, brushing down sides of pan using a pastry brush dipped in water to remove sugar crystals. Remove from heat and cool completely. Serve gelato and candied chestnuts drizzled with rosemary syrup.
Note Sweetened chestnut purée is available from select delicatessens. Sweetness may vary from brand to brand, so adjust to taste by adding caster sugar to the infused milk mixture if necessary. Candied chestnuts are available from Simon Johnson and other specialty food stores.