1 1/2 c. semisweet chocolate chips
4 Tbs. unsalted butter, at room temperature
8 ounces cream cheese, at room temperature
2 1/2 c. confectioners' sugar
2 tsp. vanilla extract
1/4 tsp. salt
2 Tbs. heavy cream
Melt chocolate chips in a bowl over simmering water until smooth, about 4 minutes. Remove bowl and let chocolate begin to cool.
Using the electric mixer, beat the butter and cream cheese on medium-low speed until the mixture is smooth and no lumps remain. Add the confectioners' sugar, vanilla and salt, and beat on low speed until smooth and fluffy.
Add the chocolate and cream and beat on low until well blended.