Flan is a custard baked in a dish with caramel on the bottom. When cooled and inverted onto a serving plate, the caramel enrobes the custard. Flan is the preeminent dessert of Spain and Latin America. It is also a favorite in France, where it is known as crème caramel.

Preheat the oven to 325°F. Have ready six 6-ounce custard cups or ramekins or a 9-inch round baking dish.

Prepare the caramelized sugar as directed in Caramel Custard, using a small heavy saucepan (do not whisk in the half-and-half). When the caramel turns deep amber, pour into the cups or baking dish. Using a potholder, immediately tilt the cups or dish to spread the caramel over the bottom and halfway up the sides.

Whisk in a large bowl just until blended:

Heat in a medium saucepan just until steaming:

Gradually whisk the hot milk into the egg mixture and stir until the sugar is dissolved. Strain the mixture through a fine-mesh sieve into a bowl or large measuring cup with a pouring lip. Stir in:

Pour into the caramel-lined cups or dish. Set the cups or dish in a deep pan large enough to accommodate them without touching each other or the sides of the pan. Set the pan on a pulled-out oven rack and add enough scalding-hot tap water to come one-half to two-thirds of the way up the sides of the cups or dish. Bake until firmly set in the center, 50 to 60 minutes for individual cups, 1 to 1 ½ hours for a single dish.

Remove the custard(s) from the water bath, let cool on a wire rack until barely warm, loosen the edges of the flan with a knife, and invert onto individual plates or a large plate (the plate for a large flan must be either broad or deep to catch all the caramel). If not serving right away, you may refrigerate, covered, for up to 2 days. To unmold, dip the cups or dish briefly in hot water before proceeding as above.