1Mix the milk and sugar.
2Add the yolks and the juice of half a lime.
3Do this through a sieve.
4Add vanilla, salt, cinnamon and grated rind of half a lime to .
5Let this mixture stand for half an hour.
6Then put on high heat until boiling.
7Turn heat to medium fire, stirring occasionally.
8When the sweet syrup is golden brown it is ready.
9Serve cold.