Porridge with g/f oats, g/f toast and marmalade, Greek yogurt with berries, egg on toast or just a coffee usually. Not big on breakfast and don't really like cereal but if I do eat it, Mesa Sunrise is my favourite.
I can't remember where I read it but basically they said scratch traditional breakfast and eat whatever you might have for lunch or dinner. Throw out the traditional ideas for breakfast. I've got two coeliac kids and one has cereal and fruit the other will have fruit or carrots and hummus.
What about omelettes, pancakes, fruit and yogurt, overnight oats (depending on how you fare with gf oats).