I have a question for you. Do you eat meals until you are STUFFED? Do you feel gross and full when you are done with your meal? If so, here are some tips to help with this:
It may take a while, but practice mindful eating. What is this you ask? It is eating slowly, and paying attention to what you are eating. This means not eating in front of the tv, while working, reading, etc. Really try and TASTE your food. Also, don't eat until you are stuffed, but comfortably full. Remember it can take 10-20 minutes for your stomach to feel full so stop when you are SATISFIED. Also, sometimes I like to have a small chocolate after one of my meals( I mean small, individually wrapped, like 2 Hershey kisses or one Ghiradelli individually wrapped dark chocolate square). This is a nice signal to your body also that your meal is done. And, you hopefully can stop at just one since you are comfortably full!
Remember to slow down and enjoy those meals!