The night before, soak white beans in a pot with 1" of water over top. On the day of, drain before using.
Heat oil in a large skillet on medium heat. Add onion and cook until tender, about 4 minutes. Add garlic, thyme, salt, and pepper. Mix well, then remove from pan and set aside.
In this pan, brown sausages well, then set aside with the onion. Brown chicken thighs, adding to the sausages and onion.
Sauté diced bacon, then transfer all ingredients except garnish to a slow cooker, stirring to combine.
Cover and cook on low for 7–8 hours. Before serving, garnish with chopped parsley and croutons.
Notes
Can also be made in a dutch oven. Bake at 350ºF for 1 1/2–2 hours, then sprinkle parsley and croutons (or breadcrumbs) and baking uncovered for 10–15 minutes.