Make Oreo cheesecake bars by pressing 30 crushed Oreo cookies and 1/4 cup of butter into a baking pan for the crust. For the filling, beat together 8 ounces of softened cream cheese, 1 cup of sugar, 1 teaspoon of vanilla, 1 cup of sour cream and four eggs. Fold more chopped Oreo cookies into the cream cheese filling, and spoon it over the Oreo crust. Bake the bars at 325 degrees Fahrenheit for 45 minutes, and chill them.
To make chocolate chip Oreo cheesecake bars, combine one package of Oreo cookies and 1/2 cup of softened butter in a food processor, and blend until the ingredients are well combined. Press this crust mixture into the bottom of a baking pan. In a bowl, cream three 8-ounce packages of softened cream cheese and mix in one 14-ounce can of sweetened condensed milk. Once a smooth batter forms, mix in three eggs and 2 teaspoons of vanilla extract. Toss 1/2 cup of mini chocolate chips with 1 teaspoon of flour, and stir them into the filling.
Pour the filling into the prepared Oreo crust, and top it with another 1/2 cup of mini chocolate chips. Bake the cheesecake bars at 300 degrees Fahrenheit for one hour, and then chill them for another hour before serving.