1. Cut the peaches in half and remove the stones. Place the peaches in a large bowl, cover with boiling water and leave for 2-3 minutes.
2. Drain the peaches, then carefully remove the skin. Using a sharp knife, halve the peaches.
3. Place the caster sugar in a saucepan and add 50 ml/ 2 fl oz water.
4. Bring the sugar mixture to the boil, stirring occasionally, until the sugar has dissolved. Boil rapidly for about 2 minutes.
5. Add the peaches and coffee essence to the pan. Remove from the heat and allow the peach mixture to cool.
6. Meanwhile mix together the Greek yogurt and custard until well combined.
7. Divide the peaches between the 4 glass dishes.
8. Spoon over the custard mixture then top with remaining peach mixture.
9. Chill for 30 minutes and then serve, decorated with peach slices, mint sprigs and a little creme fraiche.