Bring first 4 ingredients to a boil in a medium saucepan, stirring often. Boil, stirring constantly, 3 minutes. Remove from heat; add baking powder and vanilla. Beat at medium speed with an electric mixer 5 to 7 minutes or until thickened. Drizzle quickly over cake.
This icing is delicious. It tastes just like melted caramel squares. Very easy to make. Thanks for sharing.
This is great icing and easy to make, but very sweet. It has the same taste as those little caramel squares.