If I eat burgers or sandwich its lunch, if served on a plate its dinner.
If I eat it at lunchtime (noon) its lunch. If I eat at dinner time (5:00 - 8:00 pm) it's dinner. If I eat it at suppertime (after 9:00 pm) it's supper.
Doesn't matter what the food is or what it's served on - what matters is the time of day it is eaten.