Pressure cooked beans instead of directions following the Minimalist Baker instructions I also have saved here.
Used the bean water (strained through a mesh sieve after setting the beans aside) as the majority of the liquid for my soup stock. Added 3.75 cups filtered water to bring the total volume to about 3 quarts. Added celery and onions, added my ham bone from the ham I was using. Slow cooked on high for about 4 hours (2 probably would have been sufficient but I was doing other things). After pulling out the ham bone, used my immersion blender to puree some of the celery and onion.
Since I had more broth than what was called for, I included about 1.5 pounds (dry weight/pre-cooked) worth of the cooked white northern beans. Mashed up about 4 baked potatoes worth of pre-baked potato, and included about 1 pound of ham pieces. I also included about 1.5 pounds of carrot pieces.
Simmered the whole soup for about 45 minutes to cook the carrots and finish cooking the beans. Skipped the parsley.