Put half the mango in a saucepan with the sugar and 100ml water. Cook for 8-10 mins then strain through a sieve and leave the liquid to cool.

Meanwhile, pour 500ml boiling water into a large heatproof jug and add the green tea leaves. Leave to steep for 5 mins, then strain into a large glass jug and add 300ml cold water. Leave to cool completely then put into the fridge to chill.

Once cold, add the strained mango syrup to the chilled tea, along with the rest of the chopped mango, fresh mint and the lime slices. Fill up the jug with ice, stir gently and serve.