Wash and dry the strawberries, remove stalks and cut into quarters. In a large bowl, place the strawberries in alternate layers with the sugar.
Combine the lemon juice, zest and peppercorns and pour over the strawberries. Cover and leave for 30 minutes to marinate.
Pour the contents of the bowl into a large saucepan and bring to the boil for 40 minutes. Finally add the mint leav