Why did he NEED to Eat that Cookie?

You should check out HAES - Health at Every Size if you haven't already. It is a great approach to eating and understanding why it is why we eat what we eat. If focuses less on weight and more on making intuitive food choices. The emphasis is on making healthy food choices, understanding that there are many reasons why we eat what we do, and taking ownership for those choices. It is a good place to start our journey to adopting a healthier lifestyle.
I think some people interpret this approach as being a pass for those struggling with weight, but honestly, to me it is all about getting healthy regardless of what the scale says. Eating that cookie was about more than just eating a cookie. Ultimately your client made the choice to eat it. But many things influenced that choice. Understanding why he chose to eat that cookie, realizing that it was a choice and exploring his reaction to that decision are the first steps in taking ownership for your health.
In the end, if he can be honest about why he ate the cookie and honest with himself about the cost/impact of eating that cookie, he will be able to make better choices. And in the end, maybe when all things considered he may decide the choice was indeed the right one, given the situation...or not.

@HH, totally agree.
Simple ain't easily simply easy.
Absolutely nothing is wrong with that. Graet Web Site!

"You make it sound so simple. If it’s so easy, why are so many people overweight and how can you help them avoid overeating?"
Because these 'overweight' people lack the will and inner fire it takes to control themselves and tell that 'need it' voice to STFU. It's tough, and you have to work at it, but if you want to be lazy and blame yourself for 'needing' certain foods you going to be fat.
Being fat is the easy way out. In the end, only they can help themselves... unless of course you want to go door to door and fix the issue.

Great post! I always tell myself, "You ate the damn cookie, now get on with life."

All you need to do to maintain your weight is count calories. All the other stuff is an accessory. If you are counting calories, then go ahead and eat a 300 calorie cookie as long as you have a chicken breast and salad for dinner. If you end the day consuming fewer calories than you need to maintain your weight, you will lose weight.
There are all kinds of ways to make it easy to count calories. I used an application called "Lose It!" on iPhone to lose 35 pounds in less than 3 months. You just log your foods right before you eat them and so you see where that food fits into your daily budget. I ate ice cream and other treats in moderation, I didn't deny myself anything, but on days when I ate a sundae I balanced it out by eating a really low-calorie, high-protein dinner and stayed under my daily calorie budget.
The whole "needed to eat that cookie" thing is denialism. Monitor your calories and take responsibility for what you eat each day and be in control of your caloric intake and thus your weight.

Fantastic! To use one of my favorite phrases, if you do or think or feel something, own it. We all need to own that we want cookies sometimes and that we can have cookies sometimes and there shouldn't be shame or the need to validate it with "I had to..." or "I need to..." That thinking just takes the power away from us and makes us always "victims" of our circumstances.

Jarret - 5 minutes after finishing the post, I read the article about Duckett being fired - what a screw-up that was.

Ah of course, stress, and not hurting someone elses feelings, and so hungry, and eating a cookie fixed it all. I've been there. Except with a Cadbury bar. Then after I ate it, I realized I was still stressed, hungry, and still had problems. Plus it didn't taste all that great bc I had inhaled it. That was when I first recognized my food problem. Even though it was just a cookie and your client has been doing great, those reasons for eating it are not so good. I do go to a therapist to deal with my troubles around food, but that's just because I wanted the intervention of a professional with accountability and sensitivity to potential slip-ups. I have found that writing in a personal journal has helped a lot when it comes to eating bc I just "have" to. Early on, the journal helped me identify reasons for why I binged after it happened, and now that i've used it to identify triggers in my life, the journal helps me take out stresses in order to prevent mindless eating. For me, the why is as important as the what.

Hey Doug, I thought this post was going to be about Stephen Duckett, lol.
Heard about this in Alberta yet?
http://www.youtube.com/watch?v=5DxeCK5Ne_Q&feature=player_embedded