Soak the black beans in water to cover overnight. Heat 1 cup of the oil in a large heavy stock pot over low heat. Add the onions and garlic and saute until the onions are limp, about 10 minutes. Drain and rinse the beans and add to the stock pot. Add the ham bone and 6 quarts of the water. Stir in the cumin, oregano, bay leaves, salt, pepper, cayenne, and 3 T of the parsely. Heat to boiling. Reduce heat to medium and cook uncovered at a slow rolling boil for 2 hours, skimming foam from the top and stirring occasionally to prevent sticking. Place the garlic sausage in a medium-size saucepan and add the remaining 2 quarts water. Heat to boiling. Reduce heat to low and simmer for 40 minutes. Drain.

Remove casings and cut into 1/2-inch slices. Heat the remaining 1/4 cup oil in a large heavy skillet over medium heat. Add the Italian sausages and saute until browned. Remove the sausages with a slotted spoon. In the same skillet, saute the bratwurst until browned. Remove with a slotted spoon.

After 2 hours of cooking, process 2 cups of the beans in a food processor fitted with a steel blade until smooth and return to the pot. Continue to cook for 30 minutes. Add the sausages and the red peppers and cook for another 30 minutes. Remove the ham bone from the soup, shred the meat and return to the pot. Add in the chopped turkey.

Stir in the sherry, sugar, and lemon juice. Cook over medium heat until the beans are very soft and the soup is thick, 30 to 45 minutes. Stir in the remaining 5 tablespoons chopped parsley. Taste and adjust seasonings. Ladle the soup into soup bowls and dollop each serving with sour cream.