1In a bowl, mix cornflour and water without any lumps.
2In a saucepan mix thick coconut milk, sugar and cornflour mixture .
3Heat it on low flame.Let it thicken. Keep stirring. Turn off the heat.Add key lime zest.
4Let it cool well. Cover it with cling film and refrigerate for 1 hour.
5Now add the juice.Stir gently.
6In another bowl, using a hand mixer,whip the fresh cream until stiff.Add icing sugar .
9Add this to the coconut milk mixture.
10Beat on slow speed for a minute.
11Transfer it to a airtight plastic container .
12Cover it with cling film and close the lid tight.
13Freeze it for minimum 6-8 hrs.