Ever heard the expression that oil and water don't mix? Literally.
Use cinnamon extract instead. It's usually alcohol based that will mix with water. Oils also kill head retention in beers. I've learned this all too well when trying to use adjuncts with a high oil or fat content.
Beer so good, it's frightening.
2014: Seven Heavens Series One: Vilon, Mystic Melomel, Skeeter Pee.