one of the hardest things to do is realize and acknowledge that you are doing it all the time and it's not an exception.
so you need to find the point that you find most compelling. i've been eating a little more junk than usual lately and what finally got me off my butt was realizing that i was only eating a combined total of 4 servings of fruits and vegetables a day. four servings. combined. total. that's it. and i find that unacceptable. so i have been focused on getting that number back up. and one of the byproducts of eating better for me stuff is that i eat less junk.
so when you hit that heat of the moment, you need to be strict with yourself for a bit. perhaps not "i can't have this" but instead "i need to look at what i am eating as a whole and see if this fits in now." or find a special place to write down your discretionary calories and once you've used them, you've used them [so maybe a little notepad that has 300 cals at the top, and each time you get one of those sweet extras, you note it in the book so that you can see what you have used up already for the day].
if you're eating more than you need, why are you doing it? because you need to address the why of it. so if you're just wanting larger portions, make the food lower cal. in other words, if you love mac and cheese, but it's 290 cals a cup, add a box of frozen spinach to the pot of mac and that additional cup of low cal veg might bring the calories per cup of that pot down to 200 cals per cup. you'll still be getting a cup of food, but it will be a lower cal cup of food. instead of shallow frying something, lightly mist it with olive oil and bake it. if you're trying to feed an emotional hunger [mad, sad, bored, tired, happy, etc], then doing something that actually addresses the issue will help do something to solve the problem.
-google first. ask questions later.