I added the beans just a few minutes before I added the chicken. Oh, & I just drained the beans lightly - didn't rinse. I like some canned bean liquid in certain sauces, & this was one of them.
If you're going to use breasts for this recipe, you'll definitely have to cut down on the cooking time a bit. For a recipe like this, I'd probably use skin-on bone-in breasts. I think they'd be better than the skinless/boneless ones, but to each his own.