Put one gelatine leaf into a bowl of cold water to soften. Then melt it in the coffee. Incline the glasses and pour in the preparation. Set aside in the refrigerator, keeping the glasses inclined in order to set the coffee jelly.
In a saucepan, heat the cream and add the chicory. Infuse the chicory for around 10 minutes. Filter.
Put the caster sugar and cream into a mixing bowl.
Soften the two remaining gelatine leaves. Incorporate them into the sugar and cream mixture. Add the cold milk.
Remove the glasses from the refrigerator. Stand them upright and pour on the panna cotta.