Step #1 PREHEAT oven to 325°F if using a silver 9-inch springform pan (or to 300°F if using a dark nonstick 9-inch springform pan).
Step #2 Mix cookie crumbs & butter; press firmly onto bottom of pan.
Step #3 BEAT cream cheese, sugar & vanilla in large bowl with electric mixer on medium speed until well mixed.
Step #4 Add melted chocolate; mix well.
Step #5 Add eggs, 1 at a time, mixing on lowish speed after each addition just until mixed.
Step #6 Pour over crust.
Step #7 BAKE 55 min to 1 hr or until center is almost set.
Step #8 Run knife or metal spatula around rim of pan to loosen cake; cool before removing rim of pan.
Step #9 Refrigerate 4 hrs or overnight.
Step #10 Store leftover cheesecake in refrigerator.
Step #11 Dust entire surface of cooled cheesecake with cocoa powder using a wire mesh strainer.
Step #12 For a festive Valentine's Day garnish, create a heart-shaped design by topping dusted cheesecake with a heart-shaped stencil & sprinkling with powdered sugar.