I specify Toasted buckwheat for a reason. If you use plain, it cannot stand up to the long cooking time. It will turn into a mushy mess!
This dish is easily adapted to other veggies: baby kale or spinach; mushrooms, squash, celery, even just a simple lemon and cracked pepper. You could add some chopped nuts to increase the protein factor, although buckwheat is high in protein.
The time needed to prepare this dish will obviously depend on how many you are feeding. I have shown it for feeding 4 people. But this could mean 6-8 as a side dish. And it is easily cut in half or even quartered, if you just feel like making it for yourself!