I tend not to eat breakfast, but working from home, making nice oatmeal for lunch is easy and very filling -- I never need to snack before end of work and dinner. I'm sure for most people who do like to eat breakfast, it would work great as a breakfast. Everything is available at Costco in shelf/freezer-stable bulk quantities for quite cheap and at good quality, and it takes 5 minutes to make, which primarily consists of opening and closing bags, and cleaning the pot at the end -- the "cooking" is entirely passive:

- 1/4 cup sprouted oats

- bit less than a handful of frozen mango, frozen strawberries, 1 banana

- small amount of goji berries

- 1 tbsp ground flax

- 1/3 tbsp cinnamon

- 1 cup water

Pressure cook in instant pot for 10 minutes. Prepare large eating bowl with:

- 1/2 cup frozen blueberries

- 1/2 cup walnuts

Pour porridge on top and mix (the frozen berries will defrost and bring everything to almost a good eating temperature, but leaving enough time to clean the pot before it has truly cooled enough). I guessed on a few measurements since I only really measure the oats, water, and powdered ingredients and eyeball everything else. Easy to adapt for >1 person.

I'd never bother trying to find a "healthy" cereal in a box as long as I had access to basic cooking and food storage facilities.