Eggs every day -- that's the slow-burning protein component. Some carbs to fill in, as a completely carbless breakfast leaves me itching for something more all the way to lunchtime. So, cold cereal or hot, with skim milk, or a slice or two of toast. Rarely, both. Some fruit if available, sometimes I substitute 500mg vitamin C tablets. Hot cereals I often add fiber to, liking to mix for instance farina, wheat bran, added wheat germ, rolled grain, sometimes certain bulgur varieties.
Nowadays, you order Roman Meal online rather than get it in a store.
Roman Meal
Going out for breakfast, it's more elaborate: eggs and corned beef hash, eggs Benedict with sliced avocado, the carb-laden breakfasts from Denny's or IHOP, or the one place in town that regularly has a Joe's Breakfast -- robust, vitaminaceous, and capable of sustaining huge loads of black pepper and salt. Yes, the diner that serves this serves you potatoes unless you'd rather go with cottage cheese or slices of tomato.