Preheat oven to 350 degrees. Grease a 9 inch springform pan. In medium bowl, combine graham cracker crumbs, sugar, and cinnamon, and then stir in melted butter. Press into bottom and sides of springform pan. Set aside.
Cheesecake
In a large bowl, mix cream cheese with sugar until smooth. Blend in milk, and then mix in the eggs one at a time, mixing just enough to incorporate. Mix in sour cream, vanilla, and flour until smooth. Pour filling into prepared crust.
Bake in preheated oven for 1 hour. Turn the oven off, and let cake cool in oven with the door closed for 5 to 6 hours; this prevents cracking. Chill in refrigerator until serving. Better if served the day after baking.
