Pour batter into baking dish and into oven. Bake for 30-35 minutes until toothpick comes out clean. Let rest and cool. The longer these rest, the more dense they become. Which is what we want! Duh.
Once brownies have cooled, mix together pumpkin puree, coconut milk, and cinnamon in a bowl. Place the mixture in a plastic bag, cut off the end, and pipe on designs however you see fit on the brownies.
Recipe by PaleOMG - Paleo Recipes at http://paleomg.com/pumpkin-swirl-brownies/