In a small container on the stove, put 1/3 cup sugar with the water to caramelize, stirring continuously (about 4 minutes). Pour the caramel immediately into pre-greased dessert cups, in which you intend to bake the crème caramel. Beat together the eggs and egg whites and add the other 1/2 cup sugar, liqueur, espresso, salt and milk.
Beat well and distribute into the dessert cups. Put them in a water bath to bake for about 55 minutes in the oven, on not too high heat. If when you stick a knife in the middle of the crème caramel and pull it out dry, it means they are ready. Take the crème caramel out from the water bath, cover with a towel and leave it to rest for at least 4 hours.
Slide the blade of a knife around the sides of the cups, remove the crème caramels and turn them upside down into plates.