In a 2 quart saucepan, combine sugar, corn syrup, water and a few grains of salt (tiny pinch;) stir until dissolved.
Boil gently to a soft ball stage. (Soft-ball stage is when a small amount of sugar syrup is dropped into very cold water, it forms a ball that does not hold its shape when pressed with your fingers. 235-240ºF (112-116ºC.)
Beat egg whites until stiff but not dry.
Gradually pour 1/3 of the syrup over the egg whites, beating constantly.
Cook the remaining syrup to soft-crack stage. Soft-crack stage is when a small amount of sugar syrup is dropped into very cold water, it scan be stretched between your fingers and separates into hard but not brittle threads.) 270-290ºF (132-143ºC.)
Beat remaining syrup into candy mixture; continue beating.
When mixture holds its shape when dropped from a spoon, add 1 teaspoon vanilla extract.
Drop by spoonfuls onto lightly buttered or sprayed parchment paper and swirl each piece with a spoon to a peak. (If desired, place pecan half in center.)