In a large bowl mix together all the minced vegetables. It is important that the vegetables are a very small dice because they are filling the small wontons.
In a skillet, saute the shrimp in the oil until just about pink. I did not fully cook the shrimp because I feel that the steamer does the rest for me. But if you feel differently, by all means go ahead and cook the shrimp fully. The shrimp should also be chopped small, I like chopping them after they cook, it seems easier.
Once the shrimp has cooled, add it to the minced vegetables and add the salt to season.
Take each wonton square and add a small amount of filling to the center. take your index finger, wet it and trace it around the edge of each wonton (to create a seal for the wontons once they are pressed together.).
Pinch each edge of the wontons so to make a triangle, then bring each of the three tips up together to create a bundle.
Repeat steps four and five until you use up all the filling.
Prepare your steamer with the water, heat it for a minute or so, and then lay the lettuce leaves on the bottom to prevent the dumplings from sticking.
Steam the dumplings in batches for about 2-3 minutes, or until the wontons become translucent.
Enjoy! They go well with soy sauce, however, I prefer the sweeter type sauce I get with the chinese take-out, so if you can find something like that to serve the dumplings with, I would suggest it.