Step 1

In a saucepan, mix together the sugar, water and cornstarch.

Step 2

Bring it to a boil on low-medium heat and whisk constantly. This mixture needs to get fairly thick - almost like a thick pudding consistency.

Step 3

When the mixture thickens, reduce your heat to low and stir/whisk for another minute.

Step 4

Remove the mixture from the heat, place in a non-metallic bowl and add key lime juice and zest.

Step 5

Allow your key lime curd to cool and thicken at room temperature.

Step 6

Store in your fridge for up to a three days.