Chill a medium glass or metal mixing bowl in the freezer for at least 10 minutes.
Next, without shaking, remove the can of coconut milk from the fridge (after chilling for at leaset 6 hours).
Open the can of coconut milk and carefully remove the thick, creamy part on top with a spoon. (About a rounded 1/2 cup worth.) Place it in your chilled mixing bowl. Be careful to add as little of the liquid part as possible, as it can thin out your whipped cream.
Then, to that bowl add the sugar, lemon juice and lemon zest and mix on high with a hand mixer or stand mixer for about 30 seconds or until it resembles whipped cream. Avoid over mixing as much as you can.
Place the whipped cream in the fridge until ready for use. It keeps in an airtight container for about one week.