Preheat oven to 350 degrees. Line a 9x13 pan with foil and spray with cooking spray.
Make brownie mix according to package directions. Pour half of the batter into the bottom of the pan and spread to coat. Line the brownie mix with the Oreos and then top them with the remaining brownie mix.
In a large bowl, beat cream cheese and sour cream until combined and no lumps remain (your ingredients need to be at least room temperature for this!). Beat in egg and sugar. Pour over brownie mix and spread to the edges of the pan. Sprinkle Andes chips on top of the cheesecake layer.
Bake for 35-40 minutes. Cool completely before cutting. Store in refrigerator.