Combine the milk, cream and mint sprigs in a saucepan, heat to boiling, then remove the pan from the heat. Chop the chocolate and soak the gelatine in cold water. Add both to the warm mint-cream and leave for 20-30 min. so the cream absorbs the minty flavour. Refrigerate the cream for at least 4-5 hours, preferably overnight. Strain out the mint, then pour the cream into a whipping siphon. Attach a gas cartridge, shake the bottle gently and then dispense the cream.To serve
With cake or fresh fruit.