Chocolate Chunk Cheesecake

Chocolate Chunk Cheesecake
2 cups finely crushed Oreos (about 20 cookies)
2 T butter, melted
4 (8 oz) packages cream cheese, softened
1 1/2 cups sugar
4 eggs
2 tsp vanilla extract
1 3/4 cups (11.5 oz package) semisweet chocolate chunks, divided
1 1/2 cups coarsely chopped Oreos (about 14 cookies)
1/3 cup whipping cream or heavy cream

STIR together 2 cups cookie crumbs and butter; press mixture into bottom and 1/2 inch up sides of a 9-inch springform pan
BEAT softened cream cheese and sugar at medium speed with an electric mixer until blended. Add eggs, one at a time, beating just until blended after each addition. Stir in vanilla extract, 1 cup chocolate chunks, and 1 1/2 cups coarsly crushed cookies. Pour into prepared crust.
BAKE at 325 for 50-55 minutes or until center is almost set. Turn off oven; let cheesecake stand in oven, with door partially opened, for 20 minutes.
REMOVE cheesecake from oven and cool in pan on a wire rack 30 minutes. Chill cheesecake, uncovered. Once chilled, release sides of pan, cover and keep chilled.
MICROWAVE remaining 3/4 cup chocolate chunks and whipping cream in a glass bowl at High for 1 minute; stir until chocolate melts. Chill 30 minutes. Pour and spread over cheesecake to edges.