Preheat the oven to 350°F (175°C) and line an 8x8-inch baking pan with parchment paper.
In a bowl, combine Oreo cookie crumbs and melted butter until evenly mixed. Press the mixture into the bottom of the prepared pan.
Drizzle sweetened condensed milk evenly over the crust.
Sprinkle white chocolate chips, semi-sweet chocolate chips, mint chips, Andes Mint pieces, and chopped Oreos on top.
Gently press down the toppings so they adhere to the condensed milk.
Bake for 25 minutes, or until the edges are golden and the center is set.
Remove from the oven and let cool completely in the pan before cutting into bars.