Badminton question: What's the best backhand grip?

Well I have my forehand grip, or the "frying pan grip", and then there's that one grip where you use your thumb to make your backhand stronger. I don't really like this grip so I use the frying pan grip to hit all my backhands. But this makes it really hard to do a backhand smash (I really can't do one anyway, haha), and it's quite weak. Am I just holding it the wrong way? I really don't like to switch back and forth between grips, because I don't have much time.