Prepare caramel: In a saucepan over medium-low heat, combine 1/4 cup water and 3/4 cup sugar. Stir until sugar melts and simmers.

Wash down sugar crystals from the pan sides with a wet pastry brush.

Continue simmering until the sugar thickens and turns brown.

Remove from heat and carefully add 2 ice cubes to stop cooking (beware of splattering).

Coat a 9-inch baking dish or mold with the caramel, swirling to cover the sides and bottom.

Set the caramel-coated mold aside.

In a saucepan, bring milk, lemon peel, cinnamon stick, and salt to a boil.

Remove from heat and let cool slightly.

In a medium bowl, lightly beat egg yolks, egg whites, vanilla, and remaining sugar until well mixed.

Pour the slightly cooled milk into the egg mixture.

Strain the egg and milk mixture into the caramel-coated mold.

Place the flan mold inside a baking dish.

Fill the baking dish with water up to half the height of the mold (bain-marie).

Cook using one of the following methods: (1) Stovetop: cook over low-medium heat until a toothpick inserted in the center comes out dry. (2) Oven: Bake at 350 degrees for about an hour until a toothpick inserted in the center comes out dry. (3) Pressure cooker: Cook in a cup of water at 15 psi for 25 minutes.

Let cool until warm.

Place a serving dish flat against the top of the mold and invert in a fast motion to unmold.