Preheat the oven to 350F. Line two baking sheets with parchment paper.
Place the brown sugar, butter, cream cheese, and sugar in a large bowl. Use a stand mixer or hand mixer to mix until well combined, about 2 minutes. Add the egg and vanilla extract. Mix until combined, about 1 minute.
Add the flour, salt, baking powder, and baking soda. Mix on low until the flour is just combined. Add the oreo chunks and peppermint chips. Mix on low until just distributed through the dough.
Use a large (1/4 cup) cookie scoop to scoop out the dough. Place up to 6 dough balls on each baking sheet. Bake for 9-11 minutes, until the edges are just set. Let the cookies cool on the baking sheet for 10 minutes, then transfer to a cooling rack to cool completely.