1. To make crust, combine Oreos, sugar and salt. Then, stir in butter. Press mixture onto bottom of 9 x 13 baking pan.

For Filling

1. Mix cream cheese, powdered sugar and sour cream on medium high speed for five minutes.
2. Then, fold in crushed cookies.
3. Gently pour filling on top of prepared cookie crust.
4. Freeze until firm.
5. When cheesecake is firm, cut into small squares or rectangles.
6. Heat semisweet chocolate chips and oil or shortening in small sauce pan over low heat. Add more oil or shortening until chocolate is pouring consistency.
7. While chocolate is still warm, dip the squares, one by one into chocolate until completely covered. Let cool on wax paper.
8. Melt white chocolate chips in small saucepan over low heat with enough oil or shortening to reach pouring consistency.
9. With fork, drizzle melted white chocolate over cheesecake squares. Return to freezer and freeze until ready to serve. If preparing a few days or weeks ahead, keep stored in an air-tight container or resealable bag in freezer until ready to serve.