I've been thinking about your post today, and wondering whether I can articulate a response that would be consistent with what I've been learning in my NVC/Compassionate Communication practice group. In NVC, the main thing is to connect and understand one another, honoring each persons needs as equally important. The main tool for connecting and understanding is guessing which of the universal human needs underlying peoples' feelings and actions might be in play. In this case, I think what your son wants is control over his own life, including what he eats. It also sounds like you want good health for him, and also that you value respect both for people and for the work that it takes to put food on the table (i.e. not wasting).
Although I respect what NellieKatz wrote, I wouldn't want to give in, because if I were you and gave in I would feel that I was honoring his needs over my own. I also would want to show more understanding for his needs than just saying "no" although Nellie was also saying to show respect for his needs by hearing out his views. (I do agree, Nellie, that there are times when you just have to say "no" as a parent.)
So here's what I would try:
Son: I want it all! Gimme!
Mom: Wait a minute. Let's see if we can both get what we want here. (Maybe putting the packet in a pocket or something? I honestly don't know.)
Mom: It sounds like you really want the choice of what you are going to eat, and that having the whole packet would give you control over exactly how much dressing you have with your chicken, is that right?
Son: Yes. I want it all.
Mom: So you really want to be able to put lots of dressing on your chicken, just as much as you want, even the whole packet?
Mom: I really want you to have choice about what you eat and for you to enjoy your food.
Son: Good. Could I have the packet now, please?
Mom: Would you be willing to listen to what I need also?
Mom: I really want you to grow strong and healthy, because I love you so much, kiddo. Giving you that much ranch dressing does not make for a balanced meal and balanced meals help you to grow strong and healthy. Could you tell me what you just heard me say?
Son: You want me to eat less ranch dressing.
Mom: Thank you. It's not so much about the dressing and just that I want you to eat the kind of balance that will help you grow. Can you tell me what you just heard me say?
Son: You want me to eat good stuff.
Mom: Yes! A good balance. So is there a way that you can control your amount and also I get to see that you won't use so much that it's not healthy?
Son: [I'm really reaching here - I have no idea if he would say this:] O.k., let Daddy put half of it in the bowl, and I'll use as much of that as I want, o.k.?
Mom: O.k. Son. I'm glad we can both have what we want.
I know this sounds awfully involved. NVC does take time. What do you think? Do you think it might go this way? Really getting to the underlying needs can help so much.
Edited by Dancianna - 8/18/11 at 8:11pm