DD is also 15 months and eats pretty regularly - 3 meals and 2 snacks, plus 2 bf (on waking and after lunch/before nap) and bedtime bottle.
Something like this:
6:30 bf
8am breakfast
10:30 snack
12 lunch
12:30-12:45 bf (we're so bad, I bf her to sleep for naptime, bad BW!)
3pm snack
5:30-6pm supper
7pm bottle
Some days she eats big meals and small snacks, some days the other way around, some days she hardly seems to eat anything at all. I just offer and see how she does with it, some days I eat a lot of leftovers or throw a lot of food away!
She will go a lot longer without eating, especially when there's excitement, but if I lose track of time she either gets cranky around 2.5-3h between feedings or wakes in the night hungry. One of the problems is, if she's already gotten cranky she will say she does not want to eat and pitch a fit when I try to put her in the high chair, but once we get started she gobbles and settles right down. I don't wait for her to tell me she's hungry or anything, I try to stick to routine, but sometimes we do lose track of time.
We often do snacks "on the road", just throw some cheese and dried fruit in a baggie and take it in the stroller, she helps herself.
