A Cuban friend gave me this recipe and I adapted it to a pressure
 cooker (I also removed all references to olive oil).
                            CUBAN BLACK BEANS  <T>
 2   cups black beans
 5   cups water
 Put cleaned, washed beans in a 4 to 6 qt. pressure cooker.  Boil
 beans for 2 minutes; turn heat off, cover beans and let sit for 1
 Add the following ingredients:
 1   or  2 bell peppers, chopped
 l   large onion, chopped
 4   cloves garlic, minced
 1/2 tsp pepper
     salt or to taste
 1   tsp oregano
 1   bay leaf
 2   tbsp sugar
 Cook at 15 lbs pressure for 25 to 30 min.   Open cooker when the
 indicator has dropped down.
 Remove about 1/2 to 1 cup of the beans and mash; return to pot and add
 the following ingredients:
 2   tbsp vinegar
 2   tbsp red wine (cooking wine ok)
 Bring to a boil and simmer for about 20 min.
 Serve over white rice.