Put all ingredients including 2 tbsp. oil but not the sprigs or parsley in a 4- to 6-qt. slow-cooker. Add 5 cups boiling water and stir. Cover and cook until most of liquid is absorbed and beans are very tender, 2 1/4 to 3 hours on high or 4 to 4 1/2 hours on low.
Stir in 3 tbsp. parsley. Transfer to a serving dish and drizzle with more oil. Garnish with rosemary and thyme sprigs and remaining 1 tbsp. parsley.
Note: Nutritional analysis is per main-dish serving.