Sounds like you had some fresh yard long (asparagus) beans. If you pick them while they are real young, they'll be sweet,crisp and tender. E-mail me if you want to try planting some this spring. I grew some this year and I collected a few seeds to share.
I ordered some purple ones from Thailand but I guess the Airmail Customs threw them away. Oh well...

Dee

Yard long beans (aka asparagus beans, long beans) are often discussed on the Bean forum. The thread linked below may interest you for starters and there are many more.

Jim

Here is a link that might be useful: Long Beans

Try this site. I have a feeling they were yard long as you said they were about the thickness of a pencil? They are great fresh and cook quickly!

http://www.kitazawaseed.com/seeds_bean.html

Here is a link that might be useful: Kitazawa seed

It sounds like they could have been Chinese red Noodle beans, they are a type of the yard long beans. They are usually stir fried with some sesame seeds and a little soy sauce. For a good selection of them www.rareseeds.com which is Baker's Creek heirloom seeds they also have a large selection of Asian vegetable seeds. This year I'm growing the the Chinese Red Noodle I like this variety over the rest.
George W. Z5-6 Mo.