Beat egg yolks until blended. Combine yolks with condensed milk and vanilla extract in a heavy pot over low heat.
Cook stirring until thick enough to shape into balls.
This will take about 30 minutes. Let cool slightly.
Shape into marble-sized balls with buttered hand's. Set aside.
Combine sugar, water, and corn syrup for caramel in a thick saucepan placed over medium heat and tip pan from side to side until sugar melts into light brown syrup (about 12-15 minutes.)
Test by dripping syrup into a cup of cold water - it should form into a ball if caramel has reach the right consistency.
Remove from heat Dip each ball into the syrup.
Using 2 teaspoons lift the ball from syrup removing it from teaspoon to teaspoon to let excess syrup drop off .
Place on greased cookie sheet. Quickly work on the rest before caramel hardens.
Makes about 85 balls.