1 (6 ounce) package semisweet chocolate chips
1/4 cup butter
1/2 cup sour cream
1 teaspoon vanilla extract
1/4 teaspoon salt
3 cups confectioners'' sugar, sifted

In the top of a double boiler set over medium-high heat, melt chocolate and butter, stirring occasionally until smooth. Cool slightly. Place in large mixing bowl of an electric mixer.

In a small bowl, combine sour cream, vanilla extract and salt. Stir into chocolate and mix well on low speed, about 1 minute. Slowly beat in confectioners' sugar and mix to spreading consistency, about 2 minutes.

Yields 2 1/4 cups.