Try this the next time you play. A deep heavy topspin lob serve. The top spin helps to bring the ball down into the court. It looks like a slow serve but can catch the receiver out as it kicks up on bouncing. This can jam them up, put them back on their heels. It can produce a weak half court return and inhibit their progress to the kitchen line. Worth a try.

If you want to practice this or any other serve you could agree with your partner and opposing pair to allow 2 serves for a game so you can go for it on the first serve but have a second serve if necessary.