Place beans in a large bowl and add water to cover. Let soak (on the counter) overnight.
Drain beans and add to 6-quart crock pot.
Add 5 cups water, onion, ham hocks, red pepper flakes, thyme, and bay leaf.
Cover and cook on LOW 5 hours.
Remove ham hocks from crock pot. Season beans to taste with salt and pepper.
Remove meat from ham hocks, shred and return to crock pot. If beans aren't tender, cover crock pot and continue to cook 30 mins or until beans are soft.