Hard Butterscotch Candy

Directions

1. 1
   Put sugar, corn syrup, water and salt into saucepan.
2. 2
   Stir over low heat until sugar is dissolved.
3. 3
   Increase heat and cook until thermometer registers 250 degrees F, firm ball stage.
4. 4
   Add butter; cook with occasional stirring until thermometer registers 300 degrees F (brittle stage).
5. 5
   Remove from stove.
6. 6
   Add vanilla extract.
7. 7
   Pour into buttered shallow pan, making a layer 1/4 inch deep.
8. 8
   While warm, crease into squares with a blunt knife.
9. 9
   When cold, break into pieces.