Heat oven to 300F. For crust, mix crumbs and butter. Press onto bottom of a 9 inch springform pan. Bake for 5 min.
Melt chocolate chips over a double boiler. In large bowl, beat cream cheese till soft. Beat in sweetened condensed milk until smooth. Beat in eggs, one at a time. Add melted chocolate and vanilla. Pour into prepared crust. Bake 1 hour or until center is set. Turn off oven, open slightly and leave cake in oven for 30 min. Remove from oven and let cool completely.