Line a baking sheet with parchment paper, and set aside.
In a microwave safe bowl, melt the semi-sweet chocolate chips for 30 seconds at a time, stirring well at each interval.
Stop heating when there are still a few unmelted chocolate chips. You don't want to burn the chocolate as it'll turn into a hard, unusable lump. Keep stirring until the remaining chocolate chips have melted.
Pour the melted chocolate onto the parchment, and spread into an even layer with a silicon spatula.
Press the Oreo Thins into the chocolate, leaving a little space around each.
Place the baking sheet in the refrigerator to chill for 1 hour.
Next, melt the white chocolate chips using the same method as before. Again, make sure not to burn the chocolate. Stop heating when all but a few chips have melted. Then stir continuously to melt the remaining few.
Remove the chocolate/Oreo layer from the fridge and pour the melted white chocolate over top and spread out evenly.
Finally, sprinkle the crushed peppermints over the white chocolate and place back in the refrigerator for 1 more hour.
Once the candy has set, break into pieces, and enjoy!