Place cherries, lemon juice, almond extract, cinnamon and icing sugar mixture in a bowl and leave to macerate for 20 minutes

Transfer cherry mixture to a saucepan over medium-low heat and cook for 6 minutes until syrup thickens and cherries have softened

Transfer mixture to the pastry case and set aside to cool completely

Place ice cream in a food processor and pulse until smooth, then transfer mixture to 1.5L container

Crumble cherry pie in large pieces into container and gently stir through

Place in freezer until firm