1 cup water
1 cup sugar
6 egg yolks
1 (14 ounce) can sweetened condensed milk
1 cup rum
1 teaspoon vanilla extract
In a saucepan, combine water and sugar. Bring to a boil and cook for 3 minutes.
Place egg yolks in a blender and process on high speed. Slowly pour in the hot sugar water while blending (pouring too fast might curdle the yolks.) Add condensed milk, rum and vanilla. Blend until smooth. Chill in refrigerator.