• Preheat the oven to 340°F (170°C).
• We need 1/2 cup stainless steel ramekins for individual flans, and for a whole flan, a loaf pan (9×5-inch). Try not to use molds that are too deep.

Make the caramel:

• Heat the sugar and water in a deep saucepan until the mixture turns into caramel. Watch it closely as it changes color, and avoid letting it become too dark, which can make the caramel taste burnt.
• Carefully pour the caramel into your flan molds and let it cool.

Prepare the custard:

• Mix the eggs with half of the sugar in a large bowl. Stir just until combined rather than whipping the eggs.
• Heat the milk with the remaining sugar, stirring until the sugar dissolves. Remove it from the heat just before it boils.
• Slowly pour the hot milk into the egg mixture while stirring vigorously until everything is combined.
• Strain the custard mixture into the prepared molds. Avoid filling the molds all the way to the top, and cover them with aluminum foil.
• Place the molds in a water bath and bake at 340°F (170°C). Individual flans take about 30 minutes; a large flan takes about 40–50minutes. Cooking times can vary depending on your oven and mold size and depth. It'sready when, gently moving the mold, the edges look firm, and the center jiggles slightly (like soft gelatin), without appearing liquid or "watery."
• Let the flan cool, then cover and refrigerate, ideally overnight. (At least 4 hours)
• To unmold, run a knife gently around the edges of the flan. Place a serving plate upside down over the mold, then carefully turn both over. Lift the mold to reveal the custard and let the caramel sauce flow over the top.