1 cup brown sugar, firmly packed
2 tablespoons butter
1/4 cup milk
1 tablespoon light corn syrup
1/4 cup solid vegetable shortening
1/4 teaspoon salt
2 cups sifted confectioners' sugar
3 tablespoons hot milk
Combine brown sugar, butter, 1/4 cup milk and corn syrup in saucepan. Cook to 250 degrees, or until a small amount forms a hard ball in cold water. Stir constantly after mixture starts to boil. Remove from heat.
Combine vegetable shortening and salt and add confectioners' sugar gradually, creaming well. Add hot milk, then pour in hot butterscotch mixture gradually. Beat until smooth and thick enough to spread.
Makes enough icing to cover the top and sides of a 10- by 10- by 2-inch cake, or tops and sides of two 8-inch layer cakes.