Jan,
I have eaten the runner beans just as you would any string bean ,( phaseolus)
... raw while immature ,about half grown, after that they get a bit tough and less tasty
....cooked as green beans , before the seed matures inside , while still flat, rather looks like a pea pod at this stage, good stir fried or cooked (Boiled) with a bit of onion & bacon for seasoning.
....The beans can be let to fully mature ,picked, hulled, and dried , I have not eaten them in this way only because I don't grow enough to bother. if you did this they should be soaked over night before cooking like any dry bean.
I have grown the hyacinth beans but never eaten them . they have a different name ''Lablab''and I too have read some parts may be toxic
