Northern bean soup in Southern style

I like this soup because it is cheap and easy and Southern. I got the basic recipe from http://cookforgood.com/great_northern_bean_soup.html But I added seasonings.

Ingredients
1 pound dried great northern beans
6 cups of water (for cooking beans)
2 teaspoons salt
1 onion, chopped (about 1 cup)
1 medium sweet potato, diced (about 2 cups)
2 cups collard leaves, sliced into ribbons about 1/4 inch by 2 inches
2 teaspoons lemon juice (optional)
ground black pepper, if desired
Use the following seasonings--as desired (texas pete (a few dashes), dried sage, dried rosemary, Tablespoon of minced garlic, a few sprinkles of cayenne pepper
Additional water


Method


Pick over beans, removing any non-bean objects like stones or stems, and rinse well. Put in medium pot with water and salt. Cover pot and bring to a boil, then reduce heat to lowest possible boil. Cook until nearly tender, about an hour and 15 minutes.
When beans are nearly tender, peel and chop onion and add to beans. Peel and dice sweet potato and add to beans. Rinse collards well and cut leaves into ribbons about about 1/4 inch by 2 inches and add to beans. (Save tough center rib for another recipe.) Add additonal water (as much as you like) and add the garlic, rosemary, texas pete, sage. Raise heat if needed to bring to a boil again, then reduce heat to simmer for 20 minutes, until collards and sweet potatoes are tender.
Stir in lemon juice if desired and taste. Adjust seasonings as desired. If you like a thinner soup, add water.