Combine crushed cookies and margerine. Press on the bottom of a round 23 cm glass or plastic pan. Rotating pan midway through cooking; microwave on high 2 minutes. Put cream cheese and chocolate into a large glass mixing bowl. Stirring midway through cooking time, microwave on 50% 4 minutes, or until cheese is softened and chocolate is melted. Add eggs and beat with an electric mixer or whisk. Add 0.75 cup sugar and 1 tablespoon of liqueur; mix well. Pour over prepared crust. Rotating a quarter turn after every 3 minutes, microwave on 70% 10-12 minutes, or until center jiggles only slightly. Combine sour cream with remaining sugar and liqueur and spread over top of cheesecake. Microwave on 70% 1 minute. Let cool and refrigerate. Garnish top with (very cold to shave) dark chocolate shavings. Makes 9-10 servings.