What Bracha Rishona and Bracha Achrona do you make on (Kasha) buckwheat?
This confuses everyone as it has the word "wheat" in its name, but it's not related to wheat!
It's not chametz on Passover, either (although it is considered by some to be kitniyot).
Assuming it hasn't been turned into mush (rendering it shehakol), ha'adama before, and borei nefashot afterwards. (Source: Brachos.com cites The Laws of B'rachos: A Comprehensive exposition of the background and laws of blessings by Rabbi Binyomin Forst with Rabbi Aaron D. Twerski. Artscroll, p. 361 ISBN: 0-89906-220-2 (hard cover) ISBN: 0-89906-221-0 (paperback))