Would you like the dressing on your salad now or would you like it in a separate container?
You can use as much as you like if I put it in a container.
この場合、次のような言い方ができますよ。
ーWould you like the dressing on your salad now or would you like it in a separate container?
「サラダにドレッシングをお掛けして良いですか、それとも別の容器に入れてお付けしますか？」
ーYou can use as much as you like if I put it in a container.
「（ドレッシングを）容器にお入れした場合お好きな量お使いいただけます」
ご参考まで！
カナダ 
