How to Make It
Heat a large nonstick skillet over medium. Add oil to pan; swirl to coat. Add onion, carrot, turnip, celery, and garlic; cook 5 minutes or until just tender.
Place vegetable mixture in a 5-quart slow cooker. Add cannellini beans, sausage, tomatoes, chicken stock, thyme, salt, pepper, and bay leaf. Cover and cook on LOW 8 hours or until vegetables are tender.
Melt butter in a small skillet over medium. Add breadcrumbs; cook 3 minutes or until browned, stirring frequently. Remove pan from heat; stir in cheese. Stir half of breadcrumb mixture into cassoulet in slow cooker; sprinkle remaining breadcrumb mixture and parsley evenly over each serving.