Dumb question, I know, but has anyone ever simmered dark greens and
beans in the same pot before?

I ask because once upon a time I did such a thing with spinach and
pinto beans (with a hamhock and a chopped onion). The pintos were
from dry beans and the spinach was from fresh frozen. To my chagrin
and dismay, the result tasted oh-so-strongly of hot plastic. I had
done the same thing dozens of times before (and since) sans the
spinach and it had been fine, so I had fingered it as the culprit.

Does that sound right, or more like some one-off freak occurrence?

I ask because dark greens in with beans sounds good to me still. I
know I could just "try it again" with collards or spinach, but I hate
wasting food. So I ask.

Thanks in advance.

If anyone has a recipe or knows the name of a dish or stew that
incorporates these things, please let me know.

-J