Boil the rice in the water along with the sugar, the lime skin & the cinnamon stick. You should check on your rice often and add water if needed, until grains are cooked through and texture is creamy (it usually takes about 200 ml/7 Fl. oz more).
Take your pot off the fire, remove the lime peel and cinnamon stick and pour in the can of condensed milk.
Bring pudding to a slight boil again, dissolve the tablespoon of sugar and corn flour into the cup of warm buffalo milk and add it to the rest of the pudding.
Add lime zest, stir in and serve pudding into bowls.
You can rinse the rice before cooking it (using a bowl and a sieve to wash it in) but don't overdo it. When used for puddings, or risotto, you need those surface starches that help achieve a creamy texture!