Sort through beans, removing any debris or stones. Rinse briefly and add beans to a 5-qt or larger slow cooker. Add 1 tsp salt.
Add all remaining ingredients to slow cooker. Cover and cook on low for 8 hours.
Mash 1/4 - 1/3 beans and vegetables (use a potato masher, food mill or blender - don't use an immersion blender, which will grind up the sausage with it) and stir in well. Taste and add additional salt by 1/4 tsp until it tastes good to you. Serve hot with crusty bread.