Place chocolate, corn syrup, butter and 1/2 cup of whipping cream in a double boiler and simmer until the chocolate melts. Cool. Add liqueur and vanilla. Beating remaining cream and powdered sugar until stiff peaks form. Fold chocolate mixture into the whipping cream mixture in three additions. Pour pate into a mold or pan lined with plastic wrap and freeze for about 3 hours. When molded, invert pan or mold and release onto a chilled plate. Serve as desired with drizzled strawberry coulis and a fresh strawberry.