Classic Chocolate Milk Shake

Directions

1. 1
   Stir sugar and water in heavy medium saucepan over medium-low heat until sugar dissolves.
2. 2
   Increase heat and bring to boil.
3. 3
   Place cocoa in small bowl.
4. 4
   Gradually whisk in sugar syrup.
5. 5
   Return mixture to same saucepan.
6. 6
   Boil 1 minute, whisking constantly.
7. 7
   Pour into bowl.
8. 8
   Whisk in vanilla and cool completely.
9. 9
   Cover and chill until cold, at least 1 hour.
10. 10
    (Syrup can be made 1 week ahead.
11. 11
    Keep refrigerated.)
12. 12
    Pour 3 tablespoons chocolate syrup and 1 tablespoon milk into blender.
13. 13
    Add 1 1/2 cups ice cream and blend until smooth.
14. 14
    Pour into glass.
15. 15
    Repeat in 3 more batches, using 3 tablespoons syrup, 1 tablespoon milk and 1 1/2 cups ice cream for each milk shake.