In a large sauce pan heat olive oil and add sausage and onions. Saute for 1 - 2 minutes. Seperate Boy Choy stalks from green leafy parts. Dice stalks and add to sausage mixture, saute another couple of minutes until sausage is starting to brown and veggies start to soften. Drain 1 can of beans, add to mixture, add other can of beans with juice. Add Chicken stock, leafy parts of bok choy (lightly chopped) and garlic powder and black pepper. ( I don't really measure seasonings, I just eyeball it so feel free to adjust to suit your taste.) You can add a little water or more chicken stock at this point if you like a thinner consistency. Let everything simmer about 15 minutes or until leafy greans are wilted. Serves 4 nice size bowls of soups.