I was thinking of making this recipe with Chinese 5 spice powder, but don't know how much to use--any suggestions?

Do you mean you'd like to add it in addition to the other spices or in place of? If the former, then I'd add 1/2 teaspoon. Chinese five spice powder often includes cinnamon and cloves, which are already called for in this recipe. Doesn't mean you shouldn't experiment with it but that's why I suggest just 1/2 teaspoon. If you leave out the cinnamon and clove, then I'd try 1 teaspoon five spice powder.