Use food processor to turn cookies into crumbs or place cookies in a large plastic bag and smash with a rolling pin.

Stir together cookie crumbs and melted butter in a medium bowl. Transfer into a greased 9-inch springform pan. Press crumbs into bottom and halfway up the sides. Place in 350 degree oven and bake for 8 minutes. Let cool while you make filling.

Reduce oven temperature to 325 degrees.

Place 1/4 cup chocolate chips in a small bowl. Heat 1/4 cup heavy cream in a small bowl to just a simmer. Pour cream over chocolate chips. Let sit 2 minutes and then stir until smooth. Set aside.

Using and electric mixer, beat cream cheese and sugar until smooth.

Beat in cocoa powder.

Add eggs, one at a time, beating just until combined.

Stir in vanilla and melted chocolate mixture.

Pour batter onto crust. Place springform pan on a baking sheet and bake 45 to 50 minutes or until center jiggles just slightly. Cool cheesecake 10 minutes.

Make topping. Place chocolate chips in a small bowl. Heat cream in a small saucepan just until it reaches a simmer. Pour over chocolate chips. Let sit 2 minutes. Add vanilla and stir until smooth.

Spread over filling. Let sit 10 minutes. Run knife around edge of pan. Remove sides of pan. Let sit on counter to cool for 1 hour. Then refrigerate overnight.