Preheat oven to 325* You can use either a spring form pan or a 9x13" cake pan for this recipe. I have used both and they both work great.. just reduce cooking time by about 10 minutes for the 9x13 pan.
Mix crushed oreos amd butter; press firmly onto bottom of pan. bake for 10 minutes.
Beat cream cheese, sugar, vanilla with electric mixer on med. speed until well blended. Add chocolate; mix well. Add eggs 1 at a time; mixing on low speed after each addition just until blended. Pour over crust.
Bake 45-55 minutes or until center is almost set. Run knife around rim of pan to loosen cake. cool before removing rim of pan. Refrigerate 4 hours or overnight.. makes 16 servings .. Enjoy!