Caramel Icing

Directions

1. 1
   Combine margarine, brown sugar, sugar and evaporated milk in large saucepan; mix well.
2. 2
   Bring to a rolling boil over medium heat, stirring constantly.
3. 3
   Boil for 15 minutes or until mixture begins to thicken, stirring constantly; remove from heat.
4. 4
   Stir in vanilla.
5. 5
   Pour into large mixer bowl.
6. 6
   Beat at high speed until smooth.
7. 7
   Spread over cake layers.