1. Heat oven to 350 degrees F. Lightly coat a 9-inch springform pan with vegetable cooking spray.
2. For crust, combine graham cracker crumbs, the 1/4 cup sugar, cocoa and the 1 egg white in bowl; pat over bottom of pan. Bake 8 minutes; cool.
3. Reduce oven to 325 degrees F.
4. Meanwhile, for filling drain yogurt in strainer lined with coffee filter over bowl, 30 minutes. Dissolve espresso powder in water. Beat Neufchatel cream cheese and nonfat cream cheese on medium speed with electric mixer until smooth. Beat in the 3/4 cup sugar; add eggs and the 3 egg whites, 1 at a time, just until blended. Beat in yogurt, espresso, flour, and vanilla.
5. Wrap outside of springform pan with heavy-duty foil. Pour filling over crust and place in roasting pan; add enough hot water to come 1 inch up side of cheesecake. Bake 50 to 55 minutes or until center is just set.
6. Cool cheesecake in water bath. Remove; discard foil. Cover and refrigerate overnight. Remove sides of pan. Garnish with chocolate curls, if desired.