I always loved my Granny’s Navy Bean Soup; and the Senate soup is a perennial favorite. Here’s the Wiki on it:
https://en.wikipedia.org/wiki/Senate_bean_soup
If you do a google search, there are lots of recipes, some with mashed potatoes and some without. Here are two recipes on the Senate website (warning: the second ‘Dubois’ recipe makes 5 gallons ;-):
https://www.senate.gov/reference/reference_item/bean_soup.htm
I put some Boars Head Smoked Sausage in the crockpot with the Navy Beans.