In a small saucepan melt sugar over moderate heat, stirring frequently, until sugar is a dark, caramel-colored liquid. Remove from heat and pour into a 4 cup metal ring mold or 8 individual molds. Quickly turn mold to coat bottom and sides with the caramel. Let cool so caramel hardens. Heat oven to 325. Put the condensed milk, milk, eggs, egg yolks and flavorings into an electric blender. Cover and blend to mix well. Pour mixture into mold; put mold in a larger pan filled with water to depth of 1/2 inch. Bake for 1 hour. Remove from oven and remove mold from water. Cool and then refrigerate up to 2 days. Cover mold with an inverted serving platter. Hold mold and platter together and turn them over. Lift off mold. Caramel will fall as a liquid sauce over the custard.