Buckwheat is not a grain like many people think. It provides a high amount of complete protein (13 grams per 100 grams) that's supposedly better than that of soy or even fish and packs over 300 calories per 100 grams. At $2.50 for a kilo, that's a really good deal on a prime protein source. I personally just boil it and eat it with butter and vegetables, cheese, meat, or beans.
Buckwheat takes about 10 minutes in boiling water to cook. You can also soak it in warmish water for half a day and just bring it to a boil, and it'll be ready.
I'm considering making buckwheat a staple for my hike and eating between 150 and 200 grams a day for lunch or dinner. That's 20 grams of protein and lots of complex carbohydrates.