Always give the same thing

Don't need change that much. I always feed oatmeal to my tot. Some people give them cold cereal.
Once they get used to one kind of breakfast, they'll stick to it. Don't offer too much options until they're good at the regulars.
Also, don't feed too early, let them play for at least half hour after getting up.
If weather permits, go outside play for half hour or more.
Children needs intense physical/ mental activity to add appetite.
No playtime, no appetite.