Great job and smart choice to fill in the background with a starry sky. You only need a few star patterns and voila! 

Love the really stylised magical swirls coming from the cauldron, adds a lot of whimsy to the piece.

Slightly left field/tangent, I can actually imagine this being a label for some form of candle wax melt or oil. Bewitching Brew :D. Or I guess that makes it sound like a drink haha.