A highly rated recipe for Mexican flan is About Food's recipe that uses sugar, eggs, sweetened condensed milk, evaporated milk and vanilla. The recipe takes about 20 minutes to prepare and makes six mini flans.
Start by cooking 1 cup sugar in a warm pan over medium heat, stirring the sugar constantly until it begins to brown and forms a caramel. Pour 2 to 3 tablespoons of the caramel into the bottom of each of six ramekins and tilt each to get the caramel on the sides of the ramekin.
With an electric mixer or a whisk, beat together 6 eggs. Mix in a 14-ounce can of sweetened condensed milk and two 13-ounce cans of evaporated milk. Gradually mix in 1/2 cup sugar, then stir in 1 teaspoon vanilla. Pour the custard mixture into the ramekins, and place the ramekins in a large baking dish filled with 1 to 2 inches of water. Bake the flan for 45 minutes at 325 degrees Fahrenheit, until a knife inserted on the side comes out clean.
Remove the ramekins from the water bath, and allow them to cool in the refrigerator for an hour. Turn each ramekin over onto a plate, allowing the caramel sauce to pour over the flan.