One of the hardest shots in golf is the bunker shot with an extremely downhill lie. Basically the idea is to hit the ball so it comes up quickly against the slope.
To avoid having to cop out with a side chip, adopt a proper stance in order to hit the ball straight and work against the incline. Playing the ball very far back in an open stance is the key here. If the slope is really high, you could be playing it as far as your right toe. This puts your hands before the ball and will concentrate your weight on the left leg. Compensate for the loftiness you will lose in this position by opening up the blade of the club wide. This type of shot requires one to lift up the club quickly and then deposit it quickly into the sand. Strike the sand at a point closer to the ball than normal.