AFAIK different parts of the plant are used in seasoning, but only the leaves will taste like soap. The leaves have a kind of citrus flavor (so I've heard) and the root is just bitter/earthy.
The seeds are sometimes used in brewing beer, most commonly Belgian Whit style beers with the most popular of those being Blue Moon. I have the gene, and I've tried the seeds straight up when my old room mate was brewing beer, and it tastes the same as the leaf. It finally made sense why I hated all Belgian Whit style beers.