Preheat your oven to 350 degrees and rub the bottom of an 8-inch cast-iron skillet with oil.
Prepare the Enjoy Life Brownie Mix according to the package directions, using the oil and water.
Once mixed, pour the brownie into the prepared pan and bake until a tooth pick inserted 2 inches from the side of the pan comes out clean, about 30-33 minutes.
While the brownie bakes, place the mashed avocado, cocoa powder, peppermint & vanilla extracts and a pinch of salt into a SMALL food processor (mine is 3 cups) and blend until smooth, scraping down the sides as necessary.
Place the chocolate chips into a small, microwave-safe container/bowl and microwave on half power, using 30 second intervals, stirring between each interval, until smooth and melted.
Add the melted chocolate chips into the food processor and blend until smooth and combined.
Once the brownie bakes, spread on the truffle frosting and sprinkle with crushed candy canes.