Line a 9×13-inch baking pan with aluminum foil, extending the ends over the sides. Finely crush 24 Oreo cookies. Melt the butter and mix with the cookie crumbs. Press onto the bottom of the prepared baking pan to form the crust.
In a large mixing bowl, beat the cream cheese and sugar until well blended. Add the sour cream and vanilla; mix well. Add the eggs (one at a time, beating after each addition) just until blended. Chop remaining cookies into bite-sized chunks. Gently stir the chopped cookies into the batter and pour over the crust.
Bake the cheesecake for about 35-40 minutes or until the sides are set and the center is nearly set. Cool completely on a wire rack in the pan.
When the cheesecake is completely cooled, cover with plastic wrap and refrigerate for at least 2 hours. When chilled, remove the cheesecake using the foil overhang and cut the cheesecake into bite-sized pieces.
Optional Directions for Decoration
If you want to make a decorative top (drizzled with dark and white chocolate), place the cheesecake bites on a wax or parchment paper-lined baking tray. Melt the semi-sweet chocolate and white chocolate in separate bowls (you can use the microwave on 50% power, stirring frequently).
Pour the melted chocolate into two different Ziploc bags (one for the semisweet chocolate, one for the white chocolate). Snip a small corner off the corner of the bag and drizzle each chocolate over the cheesecake bars.
Chill the bars until ready to serve.
Alternately, the drizzled bites can be frozen in an airtight container for up to a month. Let them defrost in the refrigerator and serve chilled.