Preheat the oven to 350°F. Lightly grease an 8x8 square pan.
In a medium bowl, mix together the oil and sugar. Beat in the eggs, vanilla and peppermint extract until fully combined.
In a medium bowl, mix together the baking powder, cocoa powder, salt and flour.
Mix in the dry ingredients to the wet ingredients until fully incorporated. Fold in 3/4 of the chopped oreos.
Pour the batter into the prepared pan. Sprinkle the remaining oreos and crushed candy canes on top of the brownies.
Bake in the preheated oven for 23-25 minutes, or until a toothpick inserted comes out clean.
Allow to cool completely before cutting into squares.