I've found that if I skip breakfast my levels creep up and up all morning then drop very rapidly just before lunch, so I try never to miss breakfast.
I usually need to leave the house by 7.15 on weekdays so haven't got time to mess about making complicated breakfasts. I hard boil eggs and keep.them in the fridge then grab one in the morning to eat cold with a blob of mayo. I sometimes also cook Heck chicken sausages in advance and eat a couple of them cold as well.