It isn't elaborate...
Boiled Eggs, boiled the night before.
It's quick and hearty and my kids really love them just plain.

Pamela's Brownie Mix has instructions for cake. I can make 12 cupcakes from it, they are big and fluffy like those expensive coffee house ones and oh so good. I bet some of those large sugar crystals on top would make it look like a coffee house chocolate muffin. My ds2 will eat these for breakfast. They are made with eggs, so it has some protein. Actually he likes any chocolate cupcakes I make for breakfast, Rebecca Riley's recipes are good too.

Listen to your kids, these are some of the stranges request I've had for breakfast:
-chicken nuggets
-hot dogs
-fish sticks
(all GF of course, can you tell my kids are AM protein freaks?)

Anything you can do the night before or day before is good in my house. Bowls of different cut up fruits set on the table for the picking are always a winner. Some cheese slices on the side and some yogurts also go over very well.

My all time personal favorite left over is turkey with the gravy served on toast -- breakfast, lunch or dinner!!!

Let's not forget about the poor egg, it scrambles in a jiffy, can be slapped between 2 pc of toasted gf bread with a slice of cheese and ketchup for a sandwich on the run. Or just eaten scrambled.