I make my eggs sans the yolks. I do half egg whites half egg beaters, and then I make them scrambled or into an omelette.
My favorite omelette combos are:
Peppers, onions, and cheddar or American cheese
Mushrooms and cheddar
Italian breadcrumbs mixed in the eggs and small pieces of bread, and add mozerella on top when its cooking. I do it open face, more like a frittata. (The real way is to cook the cubed bread in butter first then pour on the egg and then the cheese, but I don’t fry the bread first to save some calories and fat).
My mexican relatives do a sandwich of refried beans and ham, “toasted” in one of those sandwich electric thingies.
Pizza
Quesadilla with beans, veggie and cheese
Honestly the easiest thing is to just microwave some leftover lunch/dinner food. No reason you have to have stereotypical breakfast food for breakfast.