Pineapple Chicken in Black Bean Sauce

I saw this recipe in the weightwatchers cookbook and had most of the ingredients, so I decided to try out an edited version of it.

Ingredients
Cooking spray
one small-medium onion chopped (white or yellow)
1 tbsp chopped ginger root
2 medium garlic cloves minced
1 chicken breast diced into about 1-inch cubes
1 cup canned pineapple chunks with juice
1/2 can black beans
Instructions
Before beginning cooking, put black beans with juice from can in a blender or magic bullet with a little water and blend until very smooth and runny. Add more water or chicken broth if you have it to get it smooth. (The original recipe calls for black bean sauce, but I didn't have any so I did this instead.)
Set aside.
In a saute pan, cook ginger, garlic, and onion until tender over medium heat. Add chicken and brown on both sides.
Add pineapple and juice as well as the black bean sauce mixture.Bring to a simmer and simmer until chicken is cooked through--about 5 minutes.
Serve over rice.