One way you’ll know when you’re in control of your eating rather than controlled by your eating is when you can have a taste of something you love and leave it at that. You can have a small piece of pie and enjoy it without needing more. You can have one chocolate chip cookie and not want—or need—to devour the entire bag.
Next time you decide to treat yourself to a snack or dessert, pay attention to how you feel before, during and after eating it. Is one piece enough? If not, why not? Does one serving trigger a desire to eat more? Examine whether the need to have more is really about hunger, or whether it’s an old habit you might be ready to break.