My siblings and I were fed boxed cereal about every two mornings, scrambled eggs every two or three mornings, and same with oatmeal. Pancakes or waffles on Sunday before church.
I fed my little kids pickled herring with sour cream and onions most weekday mornings, cut in small chunks. It comes in jars. Or hard-boiled eggs. I figured protein was good for kids' breakfasts, and I liked it too.
I later learned that pickled herring was considered "Jewish food" in New York. Schmaltz. I thought it was Scandinavian, but it's all sorts of things. Ukrainians love it. Who doesn't like pickled herring? It has a pow effect.
I am told that Jewish people like plain pickled herring on a bagel, with a schmear. Sounds good to me, but I would add a slice of onion. But I don't bother with breakfast anyway, other than coffee. Breakfast is for growing kids.
Do you ever wonder what breakfasts NBA players were raised on? Wheaties? Or steak? I should have had some of whatever they had.