That is the whole experiment. No shake, no counting, no tracking anything. Just something with protein in it before mid morning.

If your breakfast is currently toast or cereal
Two-to-three eggs, however you like them.
A tub of greek yoghurt, which carries roughly twice the protein of regular yoghurt for the same volume.
Baked beans on the toast you were already having.
Cottage cheese on toast, which has come back into fashion for reasons that hold up nutritionally.
Leftovers from last night, which most of the world does and we do not.
A handful of nuts alongside whatever you already have, which is the lowest effort option on the list.
If your breakfast is currently nothing
Start smaller than that. A glass of milk, a boiled egg made the night before, a handful of nuts in the car.
Skipping breakfast is a perfectly reasonable thing to do and this is not an argument against it. But if you are not eating until one in the afternoon, that is a long stretch, and the fix does not have to be a meal.
How you will know it worked
Not by a number.
The thing to notice is whether you get to eleven without thinking about food. Protein is more satiating than carbohydrate, and a breakfast that includes some of it tends to hold you differently to one that does not.
If nothing changes, nothing changes. Some people feel it immediately and some do not notice anything, and neither result means you are doing it wrong.
Why this is the version I recommend
The whole point is that it is repeatable. Consistency beats intensity in nearly everything to do with eating, and a change you make once and keep is worth more than a system you abandon in a fortnight.
One addition to one meal. That is all this is.
The takeaway: Add something with protein to breakfast. Eggs, yoghurt, beans, nuts, leftovers, whatever fits your morning. No target, no tracking. You will know it is doing something if you reach late morning without thinking about food.
The science behind this post:
- Leidy HJ, et al. (2015). The role of protein in weight loss and maintenance. American Journal of Clinical Nutrition, 101(6), 1320S-1329S. Protein increases satiety relative to carbohydrate and fat.
- Food Standards Australia New Zealand. Australian Food Composition Database. Protein content of eggs, yoghurt, legumes, nuts and dairy per common serve. foodstandards.gov.au