Line an 8" or 9" square pan with foil,
extending the foil over edges of pan.
In a heavy saucepan over low heat,
melt chocolate chips with sweetened
condensed milk and salt. Remove from heat;
stir in walnuts and vanilla.
Spread evenly into prepared pan.
Refrigerate 2 hours or until firm.
Remove from pan; place on cutting board.
Peel off foil; cut into squares.
Store loosely covered at room temperature.
Makes 5 dozen pieces or 2 pounds.