I found this recipe on FB. I have not tried it yet but plan to..
Just wanted to share....
Dried Green Bean Treats in your Oven
Preheat oven to 140 degrees F.
Spray cooking sheet with cooking spray. Open and place green beans in single layer on cooking sheet. Place green-bean cookie sheet on the middle shelf of the oven. Prop the oven door open two to three inches.
... Test green beans' readiness in four hours. Green-bean treats will be ready when they are crisp and crunchy. Remove green beans that are ready and place them in a bowl for cooling.
Keep testing, removing and rotating every hour until all green beans are done.
When green beans that have been cooling reach room temperature, put in an airtight container.