If you have a piping bag, you can use that to pipe the melted chocolate on top of the marshmallow creme. But, personally, I think a plastic bag works better in this recipe. You're only using a small amount of melted chocolate almond bark, so it's easy enough to just use a plastic bag. You can skip the bag all together and use a fork to drizzle the chocolate on top, but taking the extra time to hand pipe it just makes the pretzel so much prettier. And if you're like me and you really care about presentation when you're making a recipe, then piping is the way to go.