Preheat your oven to 350 degrees F and line a 9-inch baking pan with foil. Make the foil large enough so that it hangs over the edges of the pan. This will make it easier to lift the brownies out of the pan after baking. Spray the foil with non stick baking spray
Add the brownie mix to a medium sized bowl and whisk in the water, vegetable oil and eggs.
Pour the brownie batter into the prepared pan and spread it so that it is even and smooth.
Bake the brownies for about 32 minutes. A toothpick inserted into the center of the brownies should come out almost clean (a few crumbs on the toothpick is okay.)
Let the brownies cool completely then gently lift the brownies out of the pan using the foil.
Cut the cooled brownies into three rows that are 3 inches wide.
Cut each row into 5 triangles.
Break the curved end of the candy canes off and stick the straight candy cane into the bottom of each triangle, making it look like the christmas tree trunk.
Mix the Vanilla frosting with some green food coloring. Pipe the frosting onto the Christmas trees using a small star piping tip. You can cover the entire christmas tree brownie in frosting or just zig zag the frosting from the top of the tree to the button as if it were a string of christmas lights on the tree. You can also skip the piping bag and simply spread the green frosting over the whole brownie with a butter knife.
Add the Christmas sprinkles and M&M’s to the trees. Get creative! You can really decorate your tree however you’d like.
Enjoy the Christmas tree brownies right away or store them in an airtight container at room temperature for 3-4 days.