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Leche flan is a Filipino dessert made from a mixture of egg yolks, condensed milk, evaporated milk and vanilla flavoring. The mixture is either baked or steamed, with a layer of soft caramel on top. The finished product should be wrapped and stored in the refrigerator. Although this dessert is made with canned products that have an extended shelf life, leche flan will eventually go bad -- even when chilled.

Denser, Richer Recipe

Leche flan is a denser and richer version of other similar caramel custard recipes such as creme caramel and Mexican flan. This is because it calls for more eggs and sweetened canned condensed milk, as opposed to regular milk. Canned milks are often used in tropical climates like the Philippines where refrigeration is not readily available, since they will last last indefinitely at room temperature when unopened, and do not spoil as readily when cooked. They also contain a low water content and have a caramelized flavor that enhances the custard.

Egg Custard Considerations

The custard portion of leche flan takes on a yellow color from the egg yolks in the base mixture. In the Philippines, duck eggs are typically used, whereas chicken eggs are more commonly used in the United States. Certain recipes for leche flan require up to 12 eggs. To avoid food poisoning, egg-based custards should be cooked to at least 160 degrees Fahrenheit. Leche flan should ultimately be consumed within three to four days, but will taste best when eaten within 48 hours of cooking.

Cooking Options

Leche flan is traditionally made with a llanera, which is an oval-shaped aluminum pan about 2 inches high and 6 inches long. A full pan of flan will feed eight to 10 people comfortably. If you have fewer people or know you will not be able to eat a full pan within a few days, consider making single servings in small heat-proof dishes such as ramekins. The single servings will stay fresher longer, since you will not continuously be cutting into them.

Storing Your Leche Flan

Once your leche flan is cooked, allow it to come to room temperature before placing it in the refrigerator. You can store it in the pan it was cooked in, or put it on the plate you intend to serve it on. Cover any exposed areas with plastic wrap, getting as close to the surface as possible to prevent exposing it to air-borne bacteria. You may be tempted to freeze your flan, but this is not a dessert that keeps well in the freezer.