Yup, what everyone else said.
There are days that I "hoard" calories so that I can have a bigger dinner, but in general I've found that if I don't eat enough during the day, I wind up overeating at night. So it's better for me to plan ahead.
But it helps if you look things up in advance so that you know how much to save up. Like others said, you can use a variety of online places to do your lookups or even pick up a calorie book at the bookstore and keep it handy.
I looked up your hotdogs on The Daily Plate and here's what I came up with:
1 fat free (98%) Oscar Meyer hotdog - 40 cals
1 Kroger whole wheat hot dog bun - 140 cals
So 1 hotdog would be 180 cals. You could easily have 2 hot dogs with mustard for 360 calories total. Or have one bun, and split 2 hotdogs over it, served open faced for 220 calories.
Then have some kind of salad (cole slaw, or raw veggies, or anything w/out a creamy dressing). Just avoid things like chips and potato salad and pasta salad.
I find that if I know I'm going somewhere like a hot dog roast, I plan out ahead of time and count the calories so I know exactly what I *can* eat, rather than just guessing and then being disappointed with myself afterwards.
You're getting the idea here.
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