Bring the water with the salt, cinnamon stick and lime zest to a simmer in a medium sized sauce pan.
Add the rice, bring back to the simmer, stir. Let the rice cook until just tender, add the whole milk and bring back to the simmer, continue to cook until soft and the milk is the consistency of double cream.
Remove from the heat, remove the cinnamon stick and lime zest, stir in the sugar. If it looks a little runny but do not fear, it continues to absorb liquid, besides you want a loose, creamy texture. Let cool, refrigerate.