Fun and Funky Christmas Tree Brownies

Preheat oven to 350 degrees. Using a large sauce pan, melt butter.
Once melted, remove from heat and mix in the sugar, eggs and vanilla until combined.
In a large bowl, combine the cocoa, flour, salt and baking powder.
Gradually mix in the cocoa flour mixture into the wet ingredients until combined. Mix in the chopped walnuts.
Pour batter into the baking dish and bake for 30-35 minutes. Once baked, cool to room temperature.
Once cooled, cut brownies into trees using the and place onto a cutting board or plate so that it will be easier to decorate.
Using the standing mixer, combine the egg whites, cream of tartar, powdered sugar and vanilla and mix on medium speed until stiff peaks form.
Split the icing into 2 bowls. In the first bowl, add in a few drops of green colouring, mix until combined.
Add in some more food coloring to get the shade you want.
In the second bowl, add in black gel coloring, mix until combined. Place a little bit of icing into each piping bag
Using the remaining green icing, add 2 tablespoons of water and mix until combined. Pour the green icing into the squeeze bottle.
Using the green piping bag, pipe a line all around the trees for the edge.
Fill in the green with the thinned green icing in the squeeze bottle.
Place two eyes onto the brownies and let dry for one hour.
Using the green icing again, pipe an oval for the nose under the eyes.
Using the black icing, pipe on a smile and eye brows.